"Hi, honey!" Carol Olsen called to her husband one morning this week as marshals led him into a federal courtroom.

She sounded improbably loving for a wife FBI agents have described as the likely target of her unfaithful husband's year-long effort to research and manufacture a biological agent called ricin. It is a lethal, odorless, virtually undetectable toxin that has attracted the attention of al Qaeda terrorists and was used on an umbrella tip to kill a Bulgarian defector in 1978.

While marshals removed his handcuffs, Kenneth J. Olsen, 48, smiled wanly at his wife's hello. He was wearing powder-blue overalls bearing the logo of the Spokane County Jail, where he has been detained without bail for 10 months.

Olsen, a software engineer, father of four and a longtime scoutmaster, is being tried in this eastern Washington city of 200,000 on a federal charge of possessing a biological agent for use as a weapon. He faces a maximum sentence of life in prison.

"This is a very serious case," Assistant U.S. Attorney Earl Hicks said last summer when Olsen was arrested.

But the circumstances surrounding his arrest, detention and prosecution are also comic, puzzling and sad. Olsen's case lifts a window on adultery, familial loyalty and aggressive law enforcement in a country obsessed with terrorism.

Consider, for instance, the intense interest that FBI agents focused on Emily, the Olsen family rabbit. After Olsen was arrested, they rushed to his house in hazardous material suits, drew blood from the ailing bunny and sent it away for testing. The rabbit turned out to be ricin-free and in excellent health.

In the Spokane County jail, Olsen's cellmate turned out to be a snitch. He waited until Olsen fell asleep, copied down passages from his diary and sent them to the U.S. attorney's office, while asking for a reduced sentence in return. According to the stolen diary entries, Olsen had peculiar habits as a poison researcher.

He mixed up fruit-flavored smoothies in the same blender he used to grind up castor beans, the raw ingredients of ricin. The toxin causes vomiting, bloody diarrhea, seizures and death. ("Obviously, I used soapy water after use," Olsen wrote in his diary, according to notes taken by the cellmate.)

And there is the defendant's proud, but dispirited father-in-law. William Weise is a retired Marine Corps general from Alexandria, who came to Spokane for the trial and who says his feelings toward the government have become terribly conflicted.

"This has been a disgrace, especially for my grandkids, " said Weise, noting that his eldest grandson, Matthew Olsen, 26, is a sergeant with the 1st Marine Expeditionary Force fighting near Baghdad.

"I do understand and appreciate the government's concern about ricin," said Weise, who sat in the courtroom this week with his daughter. "But Ken never even spat on a sidewalk his entire life, and I don't think he would ever intentionally hurt any human being."

The entire case, especially Olsen's long detention without bail, strikes his wife as absurd. A federal judge denied bail on grounds that Olsen poses a serious risk to the community, even though he has no criminal record and prosecutors concede he has no connection to any terrorist group.

"If I had ever felt my life in danger or my children's lives in danger, I wouldn't have stayed with Ken," Carol Olsen said. In addition to Matthew, the Olsens have a son who attends George Washington University, as well as a daughter and son who live at home.

For 10 months after a substance suspected of being ricin was found in Olsen's office cubicle at Agilent Technologies Inc. in a Spokane suburb, Carol continued to live with Ken, while working out the marital kinks caused by his admitted affair with a local masseuse. (Besides being a software engineer, Olsen is also a licensed massage therapist.)

It took nearly a year before FBI agents got around to arresting Olsen, even though they knew of the affair and were concerned, according to court documents, that he was plotting to kill his wife.

The U.S. attorney's office here said the delay was caused by the exacting testing procedures needed to prove that the residue found on a juice jar and on 13 other items retrieved from Olsen's desk at work was ricin.

Federal prosecutors have also said their investigation was slowed by the crush of law enforcement activity after the terrorist attacks of Sept. 11, 2001.

Weise, Olsen's father-in-law, argues that Sept. 11 is playing a far greater role in this case than prosecutors will admit. The government, he said, would never have prosecuted Olsen without the hysteria brought on by the terror attacks.

"After Pearl Harbor, we put the Japanese in interment camps," Weise said. "After 9/11, it is a similar situation."

The attacks on the World Trade Center and the Pentagon were still three weeks in the future when Ken Olsen's life came unglued.

On Aug. 21, 2001, an employee at Agilent who shared a computer printer with Olson discovered an 80-page document on how to make explosives. Alarmed, he turned it over to company security, which traced it to Olsen's computer.

Company security experts then tracked Olsen's Internet activity. According to court documents, they found more than a year's worth of research into the poisoning of people with undetectable toxins, including ricin. They also found a manual titled "How to Kill." Two books were also found, "Getting Even" and "Getting Even 2."

And they discovered letters and photographs that detailed Olsen's two-year affair with Debra Davis, the masseuse. She has since told the FBI, according to court documents, that Olsen never exhibited animosity toward his wife, only resentment that he was in an unhappy marriage.

When the masseuse realized that Olsen was never going to leave Carol, court documents say, Davis broke off the relationship. That was two months before Agilent security found the love letters and the residue that turned out to be ricin.

The company fired Olsen within a week of its discovery. Worried about the safety of his wife, company officials called the Spokane County sheriff. Local authorities failed to isolate ricin in a state laboratory but passed on evidence to the FBI.

It took until late June 2002 -- 10 months after Olsen was fired at Agilent -- before federal and local law enforcement authorities, in a massive show of force in the Spokane suburbs, surrounded Olsen's car and arrested him.

In that oddly protracted interlude, Carol and Ken entered counseling and salvaged their marriage. According to court documents, Ken also began taking antidepressants as he struggled to earn a living as a part-time masseur.

The U.S. attorney's office declined to comment on its strategy in prosecuting Olsen, but in a pretrial memo filed last week in U.S. District Court here the government appeared to acknowledge that it has no evidence showing Olsen intended to kill his wife.

The memo asks the judge to instruct the jury that federal law does not require the government to establish that there was "an intended target together with an intent to kill that person."

It only needs to prove, the memo maintains, that Olsen produced and possessed ricin with a plan to "at one point use it as a weapon."

Exactly what Olsen was hoping to do with ricin is not all clear, even as explained by his own lawyers or in the jail diary entries.

"Regardless of how unorthodox my [Internet] searches were, they were for information purposes only," Olsen wrote in his diary, according to court records. The purloined diary entries will not be admissible as evidence in the trial.

"Mr. Olsen is a very intelligent and very analytic person who has an interest in a lot of things, some of which the government has tried to make look evil," said Tina Hunt, the lead defense attorney. She said the government has found only minute quantities of ricin residue, not enough to kill anyone.

"Ken may have been trying to mix up castor beans to make an aromatic balm for his massage business," said Dennis McMullen, an Olsen family attorney.

Olsen's attorneys insist that while he made stupid mistakes -- the affair, the use of a company computer to research poisons, the manufacture of ricin -- he did not commit a felony.

"What he is guilty of is being misdemeanor stupid," said McMullen. "We just hope, despite 9/11, that the good people of the area who become jurors can see that."

The Olsen trial had been scheduled to start this week, but it was delayed because the government's expert witnesses, Army bioterror specialists, were not allowed to travel to Spokane from Fort Detrick, Md. They are on 24-hour call in the event that weapons of mass destruction are found in Iraq.

Although the experts could not be here, they gave video depositions that were broadcast this week in the Spokane courtroom where Carol Olsen sat smiling at her husband.

During a noon break, as marshals led Olsen out of the courtroom in handcuffs, his wife called out:

"Have a good lunch, honey."

In Spokane, defense attorney Dennis McMullen, second from left, walks with Olsen family: sons Zane, left, and Luke; Carol Olsen, who has reconciled with her husband, Kenneth, accused of possessing the biological agent ricin for use as a weapon, and daughter Amanda.The defendant, Kenneth J. Olsen, a software engineer and scoutmaster.