He kept the capsule in a brown plastic pill bottle inside his briefcase, but nobody knew. He might have brought it to the courtroom for all seven days of his trial, or he might have had it only on the final day. It was probably a single dose, though he might have used more. He would have known precisely how much to measure out and he would have known to empty out a gelatin capsule to contain the white crystalline powder because otherwise you couldn't swallow it without the horrible, acrid taste that would make you vomit.

They had all watched him for seven days, but he never spoke. For seven days the jury of eight men and four women had heard his life dissected, his innermost thoughts exposed, his hurts, his fears, his childish neediness, and even his violent sexual fantasies that apparently drove him to become a stalker.

When the terrorist attacks struck America on September 11, the judge told the jury that the Howard County Circuit Court might be shut down the next day and that they could stay home. But the jurors voted unanimously to come in anyway to hear the closing arguments and to try to render the verdict in Case No. 13-K-00-39426, State of Maryland vs. Alan Bruce Chmurny.

Alan Chmurny was a 57-year-old scientist, a brilliant organic chemist who studied with a Nobel laureate professor at UCLA, then accumulated some 15 patents in his own name for chemical processes that he developed in three decades with several major pharmaceutical companies and start-ups. He had become a highly regarded vice president of a Maryland biotechnology company.

At 22, he had married a woman who was seven years older and had been his teacherwhen he graduated with top honors from the University of Illinois. They went off to UCLA together, where, just after they arrived in 1966, she gave birth to their only child, a daughter. He stayed married to her for 35 years, leading a seemingly normal and successful life, living in a comfortable house on a beautiful wooded acre in Frederick, with a retirement place in Colorado. His wife, also a highly accomplished chemist, testified on his behalf, saying that all these hideous accusations could not possibly be true.

As he sat day after day at the defense table, everyone studied him intently for clues. In the jury box, James Anderson was struck by how frustrated the defendant seemed. Eileen Newburn told her fellow jurors that he seemed unusually cool, unusually calm, as if he were keeping himself under control by sheer force of will. In the audience, Matthew Campbell, a veteran prosecutor who was watching parts of the trial, thought the defendant came across as particularly immature, stamping his feet, shaking his head or throwing down his pencil when he did not agree with his own lawyer or with a witness. At the bench, court reporter Shirley Reynolds also was struck by his demeanor, passing a note to a colleague that said, "He's not helping his case, acting like a know-it-all."

Chmurny did not testify in his own defense. But privately, over the four long years he stood accused of a series of escalating crimes, he had forcefully presented to his wife, his daughter, his closest friend, his succession of lawyers, his probation officers and his court-ordered psychologists the detailed elements of his version of reality.

This whole case, he repeatedly insisted, was based on a series of Kafkaesque misunderstandings and wrong-doing by the police, by the court system and mostly by his young coworker Marta Bradley and her husband. Chmurny said he had only been trying to be friends. In fact, he said, it was she who had come on to him, but now she was trying to hurt him because he had resisted her advances. His generosity, his openness, his quirky sense of humor had been horribly misinterpreted. The incriminating notes and other evidence found in his basement by the police were not his, but were mailed to him anonymously. He had never followed her home. Never stalked her. Never stole and duplicated her keys. Never broke into her house. Never stole her jewelry and lingerie. Never walked off with bags of her household garbage. And certainly, certainly never tried to poison her by pouring mercury into the air vents of her car.

That, to him, was the most ridiculous of all these absurd charges against him, the charge of attempted murder. How foolish to think that he, a chemist of vast and varied experience, would use something so amateurish and easily detectable. It made no sense that he would use mercury, he told them, because he knew many other ways, many chemicals that would work much better if you wanted to hurt someone or kill them without getting caught.

"I will never believe it was true. Not even a chance, to my dying day," Robert Kupper says of Chmurny's crimes. Kupper, the vice president of a major pharmaceutical firm, knew him for 17 years, worked with him, fished with him, went on joint family vacations, and considered Alan Chmurny his best friend. He calls him "a fun-loving guy; absolutely loved fly-fishing, horseback riding, hiking in the mountains . . . A very fair-minded guy, moderate on some issues, reasonably liberal on others . . . born and raised in Chicago; a consummate Cubs fan."

Chmurny "worshiped" his wife, Kupper says. As an executive, Kupper says, he often has worked with troubled employees and he asserts Chmurny just does not fit that profile. Chmurny rarely talked to Kupper about his legal case, saying that his lawyer would not let him, but adding, "If I could explain it to you, you wouldn't believe what is going on."

Throughout his life, Chmurny consistently impressed people with his intellect and demeanor. After a fellowship at the Massachusetts Institute of Technology, he had worked in high-level jobs for Pfizer Inc. and W.R. Grace & Co., where he repeatedly got good reviews and advanced his career. By the time of his last arrest, he had become vice president of a company in Beltsville called Biospherics Inc. "I was very taken with him," says Gilbert Levin, the firm's chief executive. "He spoke very well, presented very well, very knowledgeable."

Because he had no prior criminal record, Chmurny had been placed on probation after his initial 1997 arrest for breaking into Marta Bradley's Prince George's County home. The court ordered him to get psychological help and stay away from the Bradleys. On at least three occasions, though, Chmurny was accused of violating his probation by stalking Bradley. But he never committed a serious enough offense to be jailed. Instead, his case was continued and continued again, his probation was extended, and, eventually, further counseling was ordered.

"At that point, we did not know how disturbed he was," says Tara Harrison, a former Prince George's prosecutor. "We thought, based on his background and stature, and never being in trouble before," that probation and the threat of jail would be enough to change his behavior. "Of course, hindsight is 20-20, and if we'd known everything about him then, we never would have done that."

The succession of defense lawyers, probation officials and mental health practitioners who worked with Chmurny at various points say that they remain bound by privacy regulations and professional ethics not to divulge details of their interactions with him. Nonetheless, interviews with dozens of people who had contact with him over the years -- plus the voluminous court documents and a written record that the Bradleys kept of his activities -- suggest the outlines of a puzzling personality disorder, not easily classified. It apparently emerged only under stresses late in the life of a man who had had relatively limited experience with women in his workplace and overall.

Like a piece of cut crystal turning in the light, Chmurny's personality showed off its different facets depending on how the circumstances of life struck him. There was intensity and energy and warmth and even joviality. But he also had streaks of obsessive behavior, and paranoia, and narcissism, a fixation on the self that creates an excessive need for support and approval -- and that sparks rage and depression if those needs aren't met, according to mental health experts. Chmurny's obsession with his needs was so pronounced that one person who knew him said Chmurny could be extremely callous about hurting others: "A dog is barking. You kick the dog so it stops barking. But you do not perceive, or care, that the dog stopped barking because you hurt the dog."

Chmurny could be extremely persuasive, convincing people of his version of events by building a detailed, almost scientific explanation for his behavior, even in the face of strong contradictions. In fact, when the evidence did not match his reality, Chmurny on several occasions artfully fabricated letters, e-mails and other documents to change that reality. The result was that Alan Chmurny seemed quite credible, especially because he apparently had come to believe the altered truth himself.

Whatever the cause of Chmurny's personality disorder, the result was clear, at least to some in the jury box, such as computer scientist Scott Stewart. "Every human being has a dark side to them, and we almost always keep it locked up in a box," Stewart says. "But I think he let his out. And it was out roaming the streets late at night."

It was his crying over the deviled eggs. That was when Marta Bradley realized that the man she had known for more than a year as a troubled but friendly older colleague was really much more disturbed than she had ever imagined. She was 28, almost the same age as his daughter, when she met Chmurny at Oceanix Biosciences Corp. in Anne Arundel County, where she worked as an administrative assistant. An accomplished classical musician, she played bass for the Baltimore Opera orchestra, the Fairfax and Alexandria symphonies, and other part-time gigs, while also needing a steady day job with benefits.

She was an attractive woman, with dark hair, sharp features and sparkling green eyes. Upbeat, energetic, shapely, she came across like a cheerleader, although she'd never been one growing up in the Virginia suburbs. She'd met her husband when they were both music students at Indiana University. Scot was a jazz trumpeter, and they'd gone on the road together, playing in the orchestra for traveling musicals like "Gypsy." They'd been married nearly five years, pursuing their musical careers, living in a small place in Laurel with their two dogs, and planning on a bigger place and a family.

Oceanix had about 35 employees and they were generally a close-knit group. In the small front office, Marta Bradley and Jean Lancaster, a lab manager, often talked and gossiped with Chmurny, who was balding and graying in his early fifties. He dyed his hair and combed it over his bald spot to look more youthful. He was a lanky 6 feet and 185 pounds, an avid outdoorsman who kept in decent shape walking and hiking, in addition to his primary hobby, fly-fishing.

Alan Chmurny had been the quiet, nerdy kid with the eyeglasses in his school yearbook pictures, growing up in suburban Chicago. He was the second of two sons born to William Chmurny, a factory worker whose family hailed from Bohemia, and his wife, Anne, a vivacious woman who sold real estate after her husband died when the children were young. Alan made the National Honor Society and was a leader of the debate team. In his early life and then in his world of laboratory research, according to colleagues, Chmurny had had limited contact with women, particularly in workplace settings where the line between friendliness and flirtation can be blurred. He had few close friends, none of them women. "He'd never been exposed to a woman like that, and I think she spun his head around like it had never been spun before," says a man who knew Chmurny and asked not to be identified. "She was not doing anything improper, but he just misinterpreted it."

Chmurny enjoyed her attention. "At first, he was the kind of person you could joke around with. He was outgoing, kind of jolly," Bradley recalls. Over time, though, he began sharing his personal problems, which seemed ever mounting, and he played heavily on Bradley's sympathies. First, it was fear of cancer. He was acting quiet and withdrawn, but kept saying "never mind" when she inquired. Then he told her his doctors told him it appeared he had stomach cancer.

A few weeks later, when he was brooding again in his office, Bradley asked what was wrong and he said he'd been going through credit card receipts and determined that his wife, Gwen, was cheating on him. Later, he said he was staying with Gwen only for complicated personal reasons but that they were "living in opposite ends of the house."

Weeks later, he said his doctors had been wrong about the cancer -- and Chmurny seemed ecstatic. He told Bradley he'd met a wonderful woman named Debbie, and he was in love. He said he'd met her at a UCLA alumni function and that she was passionate, beautiful, successful and 29 years old. For several weeks, he talked intermittently about how amazing Debbie was, how he felt like a young man again.

Shortly afterward, a snapshot of a smiling Marta Bradley from the 1995 office Christmas party went missing from the company bulletin board. For some reason, she decided to ask Chmurny if he knew what happened to it. He said, "Yeah, you know, I went to go get your picture, but it wasn't there . . . Yeah, I was going to go get it and show Debbie what you look like, but it wasn't there."

Bradley recalls feeling uncomfortable, wondering why Chmurny wanted to show her picture to Debbie. Something seemed strange to her, and Bradley felt a fleeting sense that there was no Debbie, that Chmurny was making her up. Nonetheless, she occasionally would ask about Debbie, and even suggested several times that Chmurny take her on a double date with Bradley and her husband. But he always put her off. Then, in June 1996, Chmurny called Bradley at the office. "He told me he wasn't coming to work, but he said, 'Please, don't tell them why, because I don't want people to know.' And he was in tears. He was bawling on the telephone. He said, 'Debbie was killed last night in an automobile accident in San Francisco.' He was really crying, and at that point, I thought she was real."

Several weeks later, an unexplained $500 deposit appeared in Bradley's checking account. Oceanix automatically deposited her paychecks, so she asked the accounting manager and mentioned to people around her office that somebody must have made a mistake. Several days later, she got an unsigned typewritten note in the mail that said, "It's not a mistake, just think of it as your own little NEA grant," referring to the National Endowment for the Arts. Previously, Chmurny had told her he liked to help people and had the money to do it. But when she asked if he had given her the $500, he said he had no idea what she was talking about.

Chmurny intermittently seemed depressed, talked about his marriage being over, about missing Debbie, about how everything bad always seemed to happen to him. Bradley repeatedly urged him to seek counseling.

Then his cancer returned with a vengeance. "This time, he pulled me into his office, toward the end of the day, and he said, 'Before you go, I have to talk to you.' He said he was going on vacation and he had something for me. He said, 'I am going away and I may never see you again. And with everything I've been through, you've been like a daughter to me. And I want you to have something in return for that.' "

He told her his cancer had grown larger and wrapped around his internal organs, and he had to go to the Mayo Clinic for a special test in which they freeze a portion of his organs, take a sample and test the cancer. "Please don't tell anyone," he said. "I am not even telling my wife or my mother. My daughter doesn't know. I don't want to freak them out."

Then he gave her his gift. Bradley had a pair of rhinestone hoop earrings, and Chmurny said he remembered someone once asking her if they were real diamonds. She'd laughed and said, "If they were real, would I be working here?" Now Chmurny said, "I've decided because you've been like a daughter, I want you to have these," and handed her a dazzling pair of diamond earrings.

Immediately, she said, "I can't accept them, it's way too much."

But he insisted. "I absolutely want you to have them. I may never see you again. You must take them. Wear them in the [orchestra] pit. Wear them onstage at your concerts."

"I really believed him" that he was dying, Bradley recalls. "He was shaking. He had tears in his eyes. I was upset. I was in tears."

Bradley could not keep the secret and told their colleague Jean Lancaster, who became worried, called the Mayo Clinic and found that Chmurny was not there. Days later, when Chmurny called Bradley, she told him about Lancaster's effort to find him. "I remember him getting really weird on the phone, saying, 'Oh, she shouldn't have done that, she shouldn't have done that.' " The next week, he called with the good news that everything was fine, the doctors had been wrong again, and he was going on vacation.

Her growing doubts about his emotional stability were finally confirmed by the deviled eggs. A coworker named Kim was renowned for the eggs she brought to holiday parties, but Chmurny publicly insisted his were better and he organized a taste test. Kim's were plain old deviled eggs, but Chmurny's were quite elaborate, with the yolk mixture shaped by using a pastry bag, and the eggs topped with caviar. His eggs won.

The defeated Kim came into Marta Bradley's office, joking that she would never again bring her deviled eggs to an office party. Marta joked back, "Oh, Kim, please make your eggs again. I thought his were the grossest things I ever put in my mouth! Who puts caviar on deviled eggs?"

Chmurny didn't talk to Marta for several days, and then Jean Lancaster came to Bradley and said, "Marta, please, talk to him. I've never seen him like this. He was practically in tears telling me you didn't like his deviled eggs."

"I said, 'You've got to be kidding me,' and Jean says, 'Please, go talk to him.' I said, 'No, it's ridiculous.' And she says, 'Please, please' . . . So finally, I said okay. I went to his office and he literally had tears running down his face. He was crying, and I said, 'Alan, I don't know what your problem is' . . . and he said, 'It just upset me so much that you would talk behind my back like that, and your door was wide open, and that you would say such mean and hurtful things.' And I said, 'I don't know what the mean and hurtful things were. I just liked her deviled eggs better.' "

He took out his handkerchief and wept, Bradley recalls, and that is when she said to herself, There is something majorly wrong.

At Oceanix, Jean Lancaster told Bradley and Chmurny one day that she was worried about her upcoming annual evaluation. Several days later, Chmurny wrote and left in their mailboxes evaluations of each woman -- although he was not their supervisor. Lancaster's mock evaluation was straightforward praise of her work; Bradley's was not.

Listing her yearly accomplishments, Chmurny wrote: "Became a good friend to someone who needed it . . . Shared the pain . . . Shared the joy . . . Caught her friend's life with a caring heart when everything he had found was taken away in an instant. To this day she has not let it fall and break." Under strengths, he wrote, "Marta is intelligent, smart, talented beyond measure, strong, caring, funny, pretty (almost beyond measure), and forever a girl in her heart. Most exceptional is that she does not seem to be willing to give up on people when she holds them as a friend, no matter how hard they try to screw up."

Under her annual goals, he wrote, "Provide promised picture of self with dogs to reviewer, or else he'll hold his breath until he turns blue, faints, falls, and hits his head and becomes a cabbage." The evaluation concluded, "When she leaves, part of us and me will never be the same."

Bradley says she was "freaked" to read this. After the deviled egg incident, "I'd decided this was not healthy, but I'd been hoping it would just go away," she recalls. But a few days later, Chmurny threw a fit when Bradley played a recital at Catholic University on a weekend he was out of town. "He was angry. He said, 'I can't believe you would schedule it then' " -- as if his presence was crucial.

"At this stage, I knew something wasn't right," she says. "I felt he really needed me to make him feel good about himself. And I knew that whatever it was, whether he was interested in me romantically or not, that it was not healthy." She shared her concerns with her husband and with Lancaster, who both said she shouldn't be overly worried: Alan is just odd and immature. Just keep your distance, and it'll blow over. But Bradley had a growing fear that Chmurny felt he couldn't live without her, she says. "It was just snowballing."

One day in March 1997, Chmurny made a big deal about the front right tire on Bradley's car being low on air. She ran out to check her 1992 Taurus wagon and told him no, the tires were fairly new and sometimes just looked that way. But Chmurny kept insisting, so she later had her husband check it out. No problem.

That Sunday, Bradley performed at a classical concert in Baltimore and emerged to find a flat tire. Her front right. A policeman helped her put on the spare, and Scot Bradley checked out the flat. Nothing was wrong with it, so it went back on the car.

Two Sundays later, at another venue in Baltimore, Marta Bradley emerged to find the same tire flat again. Again, the tire was filled, and it was fine.

The next night, the Bradleys remember, their dogs kept barking at something outside their Laurel home. In the morning, they had a flat tire -- front right. When Scot returned for the third time to his tire dealer, they told him, "Somebody is letting the air out of your tires."

The next day at work, she talked about her persistent flat tire, Bradley says, "and Alan came running out of his office and says, 'I bet it was your front right tire. It was your front right, wasn't it? I told you it was going flat.' And at that point, at that point, I knew. I knew. There was no way to prove it, but I knew it was him."

Then Chmurny came to her and said, "I think someone is doing this to you." He insisted that she borrow and carry his air compressor. "I said, 'I don't want your air compressor.' Because at this point, I knew it was him." But he insisted on it. "No, no. Take my air compressor. I'd just feel better for you if you had it."

So she took the air compressor, and her tire problem stopped.

Bradley traveled often to play at concerts around the region, and Chmurny one day asked her friend Carol Kyte whether she knew if Marta was planning to go to Philadelphia for a weekend recital. He told her he wanted to know because "I'm worried about her. I am really worried somebody is after Marta."

During his emotional travails, Chmurny's work friends convinced him that he should seek the companionship of a dog. He got a mutt from the Frederick dog pound and chose the name Tangle. He often asked Bradley about her dogs, suggesting they should play together with his. Then, early in April 1997, Marta Bradley got an emotional handwritten two-page letter from Chmurny's dog. It was scrawled in childlike writing and signed "Love, Tangle."

"Dear Marta, I have to make this short because holding this pen makes my paws hurt. My Dad has screwed up again, hasn't he? . . . Whatever he has done, and it's probably something stupid as usual, it's okay to be really mad at him . . . I hope you know that he loves you too, even more than he loves me I think . . ."

Bradley shared the letter with her work friends, who agreed Chmurny's behavior was blossoming into something very strange. Bradley left the letter in her desk. The next day, it was gone.

That weekend, she returned home after a trip to Philadelphia and found her bedroom closet folding door off its runner. She thought at first her dogs might have done it. But then she realized she was missing much of her lingerie, regular and fancy, clean and dirty, along with a single piece of jewelry -- the diamond earrings from Alan Chmurny.

"Everything was so bizarre. We thought: the tires, the break-in, it was all so bizarre," she recalls. "It's like I knew he was doing it, but I didn't know for sure."

Back at the office on Monday after a fitful night, Bradley did not mention the break-in. Chmurny came by and remarked how tired she looked and how "Philly must have really worn you out." Bradley told him about the missing Tangle letter, asking if he took it from her desk. He emphatically denied it. The next morning, the letter was back in her desk.

The Bradleys' two dogs, Crystal and Casey, were going crazy, jumping and barking when Marta returned home from a musical performance on the night of April 11, 1997. Crystal, a normally quiet greyhound, would not stop yelping and several of her claws were broken from scratching at something.

It was another break-in. A trembling Marta Bradley took inventory of her valuables. Nothing was missing -- except her favorite tourmaline pendant, a striking piece that had been admired and commented upon several times by Alan Chmurny.

The Laurel city police took the Bradleys' report but said there was no evidence to charge Chmurny. A female police officer suggested that Marta was not telling the full story of her relationship with Chmurny, which made her so angry that Scot Bradley had to handle the rest of the police interview.

The next day, Marta told the whole story to the president of Oceanix, David Manyak, who took copies of the Tangle letter and the mock evaluation. As soon as she left Manyak's office, an agitated Chmurny demanded to know what she had been doing in there. Nothing, she said.

Days later, he followed her home at night. She saw him parked in an alley near her house and called the police. Chmurny drove away before they arrived. The next day at Oceanix, he told her, "That was really weird last night!" He explained that he happened to be in her neighborhood because he was looking to buy a house in Laurel "and I saw you, and I waved to you. Why didn't you even wave to me?"

Bradley was increasingly frightened by these strange interactions, tried to avoid him altogether, and told him he had to stay away from her. "I don't understand. I don't understand," he protested. She sensed he was almost daring her to accuse him of the burglaries. He kept prodding her for specifics and she mentioned only the theft of the diamond earrings.

Later that day, he came to her office with the appraisal form of the earrings, showing their value at more than $3,000, and told her she could use it to collect on the insurance.

By this time, the Bradleys had replaced all the locks on their rented home with deadbolts. Several days later, they both returned from music gigs on a Saturday night and found all the locks had been super-glued. The message seemed strangely clear: If I can't get in, neither can you.

The next Monday morning, Chmurny threw an envelope on Marta's desk and handed her cans of mace and pepper spray. He told her that his daughter had left the sprays at their home and he wanted her to use them for protection. In the envelope was $1,000; "Do something to protect your home," he said.

Bradley refused to accept any of it. Chmurny left in a huff, then came back and threw down a Fairfax Symphony Orchestra CD and a tape of Bradley's own playing that she had given him as gifts long before. She dismissed his tantrums as strange and immature, but when she described the most recent developments to a psychologist friend, he told her Chmurny's behavior sounded ominous. By suggesting that Marta Bradley should protect herself, her friend said, Chmurny could be saying he planned to hurt her.

Scot Bradley had been keeping his temper in check, but finally decided he had to call Chmurny. He reached him at Oceanix and, without identifying himself, said, "Stay away from my house. Stay away from my wife." He says he made no other threat. As he recalls, Chmurny responded, "What are you talking about? I don't know what you're talking about. Who is this?"

The next morning, on April 24, 1997, when Marta Bradley encountered him in a hallway, Chmurny looked flushed and shaky. "Here. This appeared in my mailbox this morning," he said, thrusting at her a stuffed manila envelope that was torn open. "I guess these things belong to you."

Inside were three of her brassieres and a sheet of cardboard with pieces of tape that held her stolen diamond earrings and the pendant. On the cardboard were cut-out newspaper headline letters that spelled: "I'M NOT THROUGH WITH YOU."

She immediately called the police. Chmurny was arrested the following week and later charged with 13 counts, including first-degree burglary, theft and harassment. He was placed on leave and several weeks later fired by Oceanix. In his final hours there, Chmurny made several trips to the paper shredder. It was not until the following year that Bradley learned that her boss, Manyak, and his wife, worried about Chmurny's intentions, had painstakingly pieced together the shredded papers, which Manyak shared with Bradley and the police.

One page had a disjointed list of things he wanted to tell Marta, including: "You were the first female friend I ever really had and were becoming one of the best friends I had. Was it wrong to love you for that and to tell you so?" And, finally, "We won't ever be friends again . . . You have been too willing to believe that everything bad that has gone on has been my responsibility. Someday you'll know you were wrong and that is too bad for you and me."

The arrest, they thought, could bring the end of the nightmare. By this point, Marta and Scot Bradley's life had been so disrupted that they'd postponed talk about having a child. They'd set up a motion detector and a video camera to record movements outside their home, and they were in fear of what Chmurny might try next. They eventually moved to a new home, had their mail routed to a postal box, and put a screening device on their telephone.

"We all like to think that we have control in our lives, and this was the biggest awakening you could ever get -- that you don't," Marta Bradley recalls. "Always having a video camera going. Always having an escort to every gig, to and from. Always carrying pepper spray. Always carrying a cell phone. Always, if I am walking by myself, carrying the cell phone with 911 already dialed and ready, and a whistle around my neck. Those were the things I could control."

The Bradleys' life actually became peaceful -- for several weeks. Then they started getting hang-up phone calls at various hours. Then Bradley found flowers in a plastic cup on the hood of her car after a concert in Fairfax. Several days later, flowers were left overnight on her desk at work. Chmurny had been banned from the premises of Oceanix, but nobody realized at the time that someone made at least six unauthorized entries to the firm after midnight by using Jean Lancaster's computer access code.

Days later, the side of Bradley's car was badly scratched up by a car key. And, carved into the driver's side window, were the words "I LOVE YOU." Whoever etched the window printed the words backwards so that Bradley could read them from the driver's seat.

Then her front windshield was smashed with a rock.

Then she got a package delivered at work with an unusual pen that she had once remarked she liked. An identical package arrived, addressed to Chmurny.

Then more flowers on her car. And more.

The Bradleys reported all this to the authorities, but they were told there was no way to prove who did it.

On February 7, 1998, Bradley was performing with a group called Concert Artists of Baltimore when, during a pause, she could hear someone walking backstage. She also heard the jangling of keys and first thought it might be a janitor. Then her heart sank as she remembered she'd left the keys to her home and car in her coat. When the performance ended, she ran backstage and her keys were gone.

Several days later, the Bradleys got a call from a woman who worked at the concert hall, telling them someone had returned the keys. Scot Bradley brought a snapshot of Chmurny with him when he went to pick them up, and the woman said it looked like the man who had dropped off the keys.

Under a plea agreement worked out by Chmurny's lawyer and Prince George's prosecutors, Chmurny admitted no guilt on the charge of harassing Bradley, but acknowledged that the state had enough evidence to convict him. The criminal charges against him would be dismissed if he complied with the order to leave Marta Bradley alone.

With the court order in place, Scott and Marta Bradley felt a little more comfortable and once again entertained thoughts of having a child. In November 1998, Marta Bradley was playing a series of performances at Baltimore's Lyric Opera House and noticed on three separate evenings that the rear window of her Taurus wagon had been unlatched.

On the night of November 18, Scot Bradley and a friend decided to stake out Marta's car while she played. If Chmurny showed up, he would be violating the terms of his probation and subject to a 90-day jail term. After two hours of watching from another car, they spotted him. As his friend dialed 911 to get the police, Scot Bradley approached Chmurny at the side of Marta's car.

"He just had this look in his eye and he wasn't really -- I don't know, it was not the same person I knew. The look on his face . . . He was possessed . . . he looked like he was someplace else," Bradley recalls.

Bradley started yelling at him: "You've been told to stay away from my wife! What are you doing here? . . . She doesn't want to have anything to do with you!"

That is when Chmurny slugged him. "I didn't see it coming at all. Just jacked my jaw." Scot Bradley got off some good shots too, leaving Chmurny's face bruised. The two men wrestled, and in the process, Bradley saw that Chmurny had something dangling from his belt. "That really scared me. First I thought it was a knife and then I saw it was handcuffs."

Bradley tried to wrestle him to the ground and mace him, but Chmurny ran off before the Baltimore police came. Since police had not witnessed the incident, they would not charge Chmurny, but Bradley filed additional charges against him the next day.

At Chmurny's trial in District Court in Baltimore, the Bradleys were astonished when he claimed that he had been invited by Marta to meet her at the opera. Chmurny produced in court a typed letter that began "Dearest Alan" and went on to say that the Bradleys had just learned another musician had burglarized their home, vandalized the car and stalked her. "I hate myself for ever thinking it was you, someone I loved and who I was sure loved me," the letter said.

To show her regret and "to show you how much we trust you," the letter said, Marta was giving her house and car keys to Alan and inviting him to enter her home in her absence. Or, the letter said, he could just meet her at her car outside the opera. "I have missed you so much. My life has not been the same without you and I still love you."

The lone handwritten word, "Marta," was a fairly accurate facsimile of her signature, which the Bradleys believed he had practiced tracing.

Chmurny also advertised in the Baltimore Sun for anyone who might have observed the November 18 altercation and he was able to obtain a witness who saw at least part of the fight and testified that Chmurny was just defending himself. On March 22, 1999, Chmurny was found not guilty of assault and harassment.

On the morning of April 5, Marta Bradley was pulling onto Route 100 on her way to Oceanix and flinched, as always, when she spotted a beige Accord. It was Chmurny. His car came up alongside hers just as she entered the highway. She grabbed her cell phone to call 911, but it wasn't working. She slowed her car, but he pulled right in front of her and slowed, too, she says. "Every time I slowed, he slowed. He just stared at me in the rearview mirror. By the time I got [to Oceanix] I was shaking. Just shaking."

A coworker suggested that if Chmurny had her car keys, he could have planted a tracking device in her Taurus, so they went outside to search her car. There was no tracking device, but tucked into a crevice in the rear seat they found several colored electrical wires along with a handwritten note on Fairfax Symphony stationery. The note said, "Mart, I made the pipe bomb/packages like you asked. They are all deadly once you connect the batteries . . . The one with the motion-detector is very trickey!! You have to turn on the timer before you plug it in, or else it will go off immediately. I showed this all to Scot too . . . Please be careful with this [expletive]. I love you."

Anne Arundel County police evacuated Oceanix and searched the car. They took the note, but later told the Bradleys they did not have enough evidence to charge Chmurny.

By now, Chmurny had stalked Marta Bradley in five different jurisdictions, so each time the local cops and judges were not aware of the full history. Midway through her first pregnancy, Marta Bradley, was fearful and depressed because of Chmurny's ability to evade the law, and she prayed he'd be stopped.

On July 16, 1999, Alan Chmurny went to the Frederick County Commissioners office and swore out a handwritten three-page criminal complaint accusing the Bradleys of telephone harassment and repeated threats of violence. To support his charges, Chmurny tried to introduce as evidence the "Dearest Alan" letter, which apparently had helped acquit him in Baltimore. Now, he tried to use it as proof that the Bradleys had lured him to Baltimore to assault him. Chmurny also produced his telephone "Caller ID" records, which showed more than a dozen calls ostensibly from the Bradleys' phone to his home in Frederick between 1 a.m. and 4 a.m. over a period of weeks. He said both Marta and Scot had been harassing him and threatened that "they would blow me away along with my wife, my dog and my property, and that we should think about that every time we turned the ignition key in any of our cars."

The case was assigned to Kirsten Daggett, an assistant state's attorney for Frederick, who recalls preferring to conduct her interviews of Chmurny by phone rather than in person. "I was a little intimidated to meet with him," she says, "because something was just not right." Chmurny was "very adamant about his position that she was harassing him," Daggett says. "He seemed like he really believed it, just the way he was talking."

After she contacted the Bradleys and their lawyer, Daggett received a copy of their voluminous file outlining the entire strange history. "It was like a murder-

mystery novel. I took it home. It was pages and pages . . . and I couldn't put it down," Daggett says. She became convinced Chmurny had fabricated the evidence, including the Caller ID. The alleged late-night telephone threats would have been toll calls from Laurel to Frederick on the Bradleys' phone bill, but the Bradleys produced telephone records showing that the calls never appeared on their bill. An investigation by the phone company suggested that the calls were actually made by someone using an extension phone from the phone box on the outside of their house. Short hang-up calls would have registered on Chmurny's Caller ID, but not on the Bradleys' phone bill.

"It was creepy," Daggett says, "and kind of ingenious." She decided to drop the charges.

The Bradleys by now had moved to a new home in Howard County and hoped it would be harder for Chmurny to find them. They celebrated the birth of a daughter in September 1999 and were able to enjoy their longest period of respite from their ordeal. "We were sure he was lurking," Marta Bradley says, "but for about five months, no sign of him."

On April 16, 2000, Marta Bradley went out to her car to retrieve documents she needed for her last-minute income-tax filing. On the front seats of her car, she saw a scattering of tiny silver balls that she initially thought were sprinkles from cake decorations. But when she touched them, they seemed to disintegrate. Then she saw traces of the substance near the car's air vents and on the floor. She called Oceanix and then the police.

Mercury in liquid form is toxic, but not necessarily lethal. In a vapor state, however, it is odorless, colorless and deadly, entering the lungs, lodging in the bloodstream and gradually accumulating in internal organs. Vaporized in a car's heating system, it would attack the liver and kidneys and eventually cause delirium, memory loss, hallucinations and ultimately death. The level found in Bradley's car was initially measured by the Maryland Department of the Environment at 400 times the dose considered safe for humans.

When he got the report of attempted mercury poisoning, Howard County Det. Glenn Case was skeptical. "I thought, 'This is kind of weird. Who would do something like this?' I questioned the authenticity of it," Case says. "But in a few minutes of meeting with her, I knew."

Case, a 12-year police veteran, decided that this was a most unusual and crafty assailant and that it would be pointless to question Chmurny. Instead, he decided to try to set a trap. The Bradleys' insurance company had declared the poisoned car a total loss, but Case arranged to leave it near their house in a spot where it could be easily observed -- by a hidden camera with night vision. Police and the Bradleys each set up unmanned cameras in upstairs bedrooms, both trained on the Taurus in hopes Chmurny would return. The Bradleys also set up their motion detector, designed to trigger a loud radio if anyone came walking around the house late at night.

Chmurny, meanwhile, mostly unemployed for more than two years, had recently been hired as a vice president and new business manager of Biospherics in Beltsville. He'd gotten the job based on impressive credentials that omitted all references to Oceanix. And now, he was a rising star. On May 22, 2000, Chmurny addressed the firm's stockholders, speaking enthusiastically about a safe-for-humans pesticide and a low-calorie sweetener, proj-ects that he headed. According to CEO Gilbert Levin, Chmurny gave such a terrific presentation at the firm's annual meeting that "everyone congratulated him."

That was Chmurny's day job, but his nights were free. Periodically, Scot Bradley would fast-forward through the eight-hour videotapes, hoping for a glimpse of Chmurny's nighttime prowling. The Bradleys also alerted their neighbors to please watch out for strangers at night.

One night in late May, her baby daughter woke her in the middle of the night and Marta took her downstairs to nurse, "and it had gotten to where I could just not stand it anymore. I was rocking her, and I had one of those conversations with God, where I said, 'What am I doing wrong? What am I doing wrong?' . . . It was a self-pity kind of thing, and I prayed, 'Please let this end.' What was so weird, I remember I prayed specifically, 'Please let somebody see him. Please let there be a witness, someone other than Scot or I.' "

The next night, May 31, 2000, somebody saw him.

A 21-year-old neighbor driving home just before 2 a.m. spotted someone tampering with Marta's car, called the police and walked over to meet the police at the Bradleys'. Marta and Scot were awakened when the motion detector triggered the blaring radio, and they were ecstatic.

Sure enough, at 1:50 a.m. the night-

vision videotape had captured the grainy illuminated image of a tall, slender man wearing a light jacket and baseball cap lurking near the car. When Scot hurriedly fast-forwarded through the previous nights' tapes, the same man also appeared in the early morning hours, at 2:23 a.m. on May 30, 1:48 a.m. on May 29, and 2:49 a.m. on May 26. The images were dark and blurry, but they were positive it was Chmurny.

Police created a "photo lineup" of six white males in their late fifties, and Case showed them to the Bradleys' neighbor, who picked No. 4 as the man she saw. It was Chmurny. Two days later, police arrested him.

This time, a judge ordered Chmurny to wear an electronic ankle bracelet that prevented him from leaving his house without permission of his probation officer. But Marta Bradley was so frightened that she packed her bags and left with the baby to visit her parents in Florida, staying there for more than a month. "I thought, if he did get out, if he decided to do that, it would be the last time he would get out," she says, "because I felt that would be the time he came to kill me."

They found his writings in his cluttered basement, inside a black satchel that prosecutors later called his "stalking bag." One page held a 700-word sexually explicit ode to Marta that began: "Here's a riddle for you. What's the difference between Marta Bradley and a female bass player that is going to be raped, castrated, have her face mutilated, and then have all her fingers on both hands cut off? Answer: There is no difference." The "riddle letter" went on to graphic descriptions of his break-ins to her bedroom, his fantasies about her body parts and his violent sexual threats.

That was only one piece in the pile of evidence police found in executing search warrants of Chmurny's home and car on the day of his arrest, June 2, 2000. Chmurny also had photographs of Marta Bradley, typewritten schedules of her work hours and her musical appearances, printouts of her e-mails and Internet search maps to her home -- although Chmurny had told Det. Case he didn't even know where she lived. Police also found the eight duplicate keys that fit the Bradleys' former home and their two cars, along with lock-picking tools. They retrieved a plastic bag that held the Bradleys' old ATM receipts and locks of hair that appeared to match that of Marta Bradley, who cut her own hair at home and threw it in the trash. They also found a jacket and baseball cap that appeared to match those worn by the man in the night-vision videotapes. And there were two sheets of paper with large computer-printed warnings: "YOU DON'T HAVE LONG" and "YOU ARE DEAD."

In Chmurny's car, they found what Case called "the smoking gun," a plastic bottle labeled "Mercury Waste" that still held some mercury.

While the search warrants were being executed, Case seized the chance to talk to Chmurny's wife, Gwendolyn. She immediately insisted that her husband was being framed. "The Bradleys are telling lies," said Gwendolyn Chmurny, a white-haired woman of 64. Case asked her how she could explain the fact that credit card records obtained by the police showed that many of the late-night stalkings happened to occur during the precise periods when Gwendolyn, a scientist at the National Cancer Institute, was away on out-of-state trips.

"The Bradleys must know my travel schedule," she told Case. She maintained that the Bradleys had staged the stalking incidents, planted the mercury in their own car and in Chmurny's, and sent the incriminating material to the Chmurnys' home.

At her husband's trial last September, Gwendolyn Chmurny attempted to make her case to the jurors, telling them, for example, that her husband kept Marta Bradley's concert schedule so that he'd know exactly where she was, so he could be sure not to violate the court order against contacting her. Such explanations showed that Alan Chmurny "snookered his wife" into believing his lies and fantasies, prosecutor Jim Dietrich told the jury in his closing argument. "Ladies and gentlemen, don't let him snooker you."

The jury stayed out for more than four hours, talking, examining evidence, and repeatedly viewing the night-vision videotapes. Chmurny's lawyers, Dino Flores and Steven Kupferberg, told him earlier in the day that they were optimistic that they had raised enough reasonable doubt. Had the prosecution proven that Chmurny actually wrote the riddle letter? Did the mercury found in the two cars definitively match? How could they be positive that it was, in fact, Chmurny in the dark, grainy videos?

The police videotape was of such poor quality that the Bradleys' own tapes had to be introduced as evidence. The images are disturbing but almost comical. The tall thin man in the light jacket and baseball cap stands in darkness, peering at the car. He walks back and forth on the far sidewalk, afraid to venture toward the car. Then he does. He walks oddly, stiffly, with his arms straight at his sides and not moving. He approaches the car, touches the door handle, and the dome light goes on. He retreats. He walks back and forth past the car. One night, he gets in the car and sits there for several minutes. Another night, garbage night, he bypasses the Taurus and walks off with two of the Bradleys' white plastic garbage bags. And finally, another night, a flood of headlights illuminates him at 1:50 a.m. on May 31, and he scurries quickly out of the picture.

For his defense, Chmurny apparently planned to have one ace up his sleeve. His lawyers subpoenaed Marta Bradley's personnel records from Oceanix, which included a six-page single-spaced narrative that Bradley wrote called "History of Relationship with Alan B. Chmurny." But after he got the subpoena last June, Manyak, the Oceanix president, reviewed her file and as he reread her narrative, he was stunned to realize the original had been replaced with a virtually identical but cleverly altered document. It had mostly the same sentences and paragraphs, had been typed in the same font, and laid out to look identical -- but inserted in it were numerous fantasy passages apparently written by Chmurny.

The original, for example, mentions Bradley's suspicions that Chmurny stole her photo from the company bulletin board. But the altered letter adds: "This was OK though. I liked the idea of his having my picture because I found myself having strong feelings for him. It was strange because we were both married and because of the difference in our ages. But I tried to avoid doing anything to show him or anyone else that I cared for him." The altered version also adds this scene: "I remember working late one night with Alan on a grant application and asking him to scratch my back under my bra. There was something about the feelings I had then with his hands on my back that made me wish things could be different between us."

Manyak had copies of the original, which he returned to Bradley's file, along with a new two-page memo he wrote, suggesting that Chmurny had made unauthorized entry to Oceanix and substituted the phony document. Chmurny's defense team never tried to use it.

Finally, just after 5 p.m. on September 12, the jury filed back into the courtroom and, as Chmurny stood in his dark gray suit and Halston tie to face them, the verdict was delivered: guilty on five of six counts. Chmurny's impassive expression did not change. The jurors were then polled individually to ask if they agreed. Chmurny had opened his briefcase and taken something out of it. As the jury began to file out, Chmurny swiveled in his chair and spoke to his wife and daughter in the front row. "Goodbye . . . I love you," he said, and murmured something about how it would be okay.

Flores, his defense lawyer, thought it odd that he was saying goodbye because he was not necessarily going to be jailed immediately.

Then Chmurny took a paper cup with water and swallowed something.

"What was that?" Flores asked.

"A tranquilizer," Chmurny said.

Flores then told him that the judge would set a date for sentencing and they would try to have him remain free on bond until then.

"Thank you," Chmurny said, shaking his hand. Then he added, "I'm dead. It was cyanide."

Flores said he would get help.

"Don't bother," Chmurny said.

The lawyer immediately asked Judge Raymond J. Kane Jr. if he could approach the bench, and whispered, "My client has indicated to me he just took a cyanide pill . . ."

Kane ordered the sheriffs to get Chmurny out of the courtroom and to call 911. Court reporter Shirley Reynolds made the call, and, with an ambulance on the way, she was connected to the state poison center. She thought Chmurny looked okay, but then he started to vomit. They gave him a garbage pail. The poison center asked her to try to confirm that it was cyanide, so she asked Chmurny.

"I didn't take anything," he replied. His face, she recalls, was "totally blank, just totally blank and he was totally calm."

So Reynolds repeated her question urgently. "Mr. Chmurny, I saw you take something," she recalls saying. "But he just stared at me."

Then Chmurny's face turned red, his eyes rolled up into his head and he went into convulsions. Cyanide, one of the most rapidly acting of all poisons, had begun to asphyxiate him. In the stomach, it turns into hydrogen cyanide gas, the same substance used in gas chambers. It blocks the enzymes that allow the body to use oxygen, essentially creating a chemical suffocation. Only a small pinch of cyanide crystals is enough to kill, often within a few minutes -- but not always. Fire department emergency medics hooked him up to an IV and rushed him out to the ambulance. On the phone, the poison center official urgently warned Reynolds that nobody should try mouth-to-mouth resuscitation.

Marta and Scot Bradley had been too nervous to stay at the courthouse. When prosecutor Jim Dietrich called their home, they immediately put him on the telephone speaker and they whooped and laughed and hugged and cried at the news of the verdict. Then Dietrich told them about the apparent suicide attempt, which they initially did not believe. Then a later call informed them it appeared to be true.

"It was such a weird feeling," Marta says. "It was unsettling, and disturbing, like all he had done for the previous four years."

At Howard County General Hospital, emergency room doctors and nurses worked feverishly to try to save him, administering a cyanide kit that can reverse the effects, if it's not too late. Outside in the waiting area, Gwendolyn Chmurny told a reporter, "He's a good man. They planted evidence. Everybody is lying." Later she told Det. Vickie Shaffer that she didn't like dealing with the police because they always lied, and "everything was a conspiracy."

The doctors were able to keep Alan Chmurny alive more than 18 hours, but there was no way to reverse the damage of oxygen deprivation to his brain. He was declared dead at 1:55 the following afternoon.

Gwendolyn Chmurny would not agree to be interviewed for this story. Neither would her daughter, whose birth name was Linda Chmurny but whose married name became Chmurny Newton because she was determined to keep her rare family name alive. "We need it all to go away," the daughter says of the family's decision to decline interviews. "It was so scary and so unbelievable. We just want to get on with our lives."

Death was among Alan Chmurny's obsessions. "He often told me that he didn't know how he could continue living," Marta Bradley wrote to a circuit court judge in 1999, trying to convince him that Chmurny was dangerous. "I felt very sorry for him at the time. I tried to listen to his problems, because he told me he did not have anyone to talk to."

Chmurny once engaged her in a lengthy conversation about death, prompted by the demise of a close friend of his who had cancer. "Aren't you afraid to die?" she recalls him asking. When she explained that her belief in God helped her, he replied, "I don't believe any of that stuff . . . No, I don't think there's a God." When the conversation turned to the idea of Heaven, she says, Chmurny said he wished he could believe in it.

As the conversation went on, Bradley says, she came to realize that he was not really very troubled about his friend's death as much as the prospect of his own. "I think he was scared," she recalls years later. "Death definitely was something he was afraid of."

Chmurny clearly knew, though, that he was going to die that day in court. He left behind a brief suicide note, according to his friend Robert Kupper, who declined to discuss its details, except to say that it spoke about Chmurny's wife, his daughter and his dog. Just as his actions in life remained a mystery to the people who thought they knew him, so too his motivation in ending his life was also left unclear. Kupper says, "He said he simply could not take it anymore."

Postscript: On December 29, the Bradleys filed a $6 million lawsuit, their lawyer said, "because they essentially lost the first years of their marriage due to Alan Chmurny's reign of terror." A Chmurny family lawyer called the suit against the Chmurny estate "salt in the wound for Mrs. Chmurny."

Peter Perl is a Magazine staff writer. Staff researcher Bobbye Pratt contributed to this article. Perl will be fielding questions and comments about this article at 1 p.m. Monday on www.washingtonpost.com/liveonline.