Not long before police say Brittany Norwood stabbed and bludgeoned Jayna Murray to death last month inside the Lululemon Athletica store in downtown Bethesda’s high-end shopping district, the two were the perfect sales team.

Murray was showing regular customer Janay Carlson items from the store’s posh running collection when Norwood walked over to chat up Carlson and help put her at ease. Norwood brought up a top Carlson had recently bought at the store.

“When that shirt first came out, I wasn’t sure about it. You’re changing my mind,” Norwood said, according to Carlson’s recollections.

Carlson stayed and chatted awhile before walking out with new running pants, a running jacket, a shirt and a headband.

There was absolutely nothing wrong inside Lululemon, said Carlson, who was in the store for about an hour and, at times, was the only customer. Norwood was smiling, left briefly to grab some takeout food and talked about the diminishing lines for the iPad 2 at the Apple Store next door.

“It must have went wrong fast,” Carlson said.

What exactly went wrong, and why, is puzzling even to longtime detectives. Friends and former co-workers described Norwood as athletic, funny and engaging. Neither they nor police were aware of any past violence or mental illness. Police also said they did not know of any animosity between Norwood and Murray.

Murray’s slaying and the story police say Norwood concocted to cover her tracks shocked the merchants and customers in the shops along Bethesda Row.

At 9 p.m. March 11, about two hours after Carlson left the store, Norwood, 28, and Murray, 30, shut the front doors and began closing for the night. Before leaving, they checked each other’s bags, a common anti-theft procedure at Lululemon and other retail chains, law enforcement officials said.

Murray saw store items in Norwood’s bag, the officials said. Murray walked to her car and called her store manager, who said she would deal with it the next morning. It was just before 10 p.m., and minutes later, police say, Murray got a call from Norwood saying that she had left her wallet in the store and asking Murray to let her in to get it.

Detectives have different theories about the confrontation that occurred after the two got back to the store.

Perhaps Norwood, not knowing that Murray had called the manager, used the wallet as a ruse to get her back to the store and then tried to persuade her to play down what she had found in the bag. “That conversation didn’t go well,” said a law enforcement official with knowledge of the case who, like other unidentified sources, spoke on the condition of anonymity because of the ongoing investigation. “Brittany had no chance of convincing Jayna to bury the truth.”

Another official described an alternate theory: Once inside the store, Murray told Norwood that she had called the manager. “When she found out, she lost it,” he said.

Either way, the two began screaming at each other — so loudly that employees in the Apple Store would later tell police they heard them, according to police charging documents. The two fought — Norwood, a 5-foot- 2, 120-pound workout fiend, and Murray, 35 pounds heavier and just as athletic.

At some point during the yelling, Norwood used objects she found in the store to pummel and stab Murray, authorities say. Murray’s skull was crushed and her spinal cord was severed, Montgomery County State’s Attorney John McCarthy said in a recent court hearing.

Authorities have found theft accusations leveled against Norwood in the past. But nothing igniting a reaction like this. “That outburst is coming out of left field,” a police source said.

“There was definitely rage,” said Drew Tracy, a Montgomery County assistant police chief and head of the department’s investigative services bureau.

Norwood has not told authorities what happened that night, police say. She initially told detectives that two masked men slipped into the store after closing and sexually assaulted both women, laughing as they did so, according to court records and sources with knowledge of the case.

Norwood remains in the Montgomery jail, charged with first-degree murder. She has not responded to a letter seeking comment. Her attorneys declined to comment.

Beyond a father’s belief

Inside Foam Rubber City, the furniture upholstery and fabric business that Norwood’s father runs in an industrial area of Kent, Wash., Earl Norwood shook his head.

“It’s beyond belief,” he said.

Asked whether he could imagine his daughter doing what police allege she did, tears welled in his eyes. “No. Under no circumstances,” he said. He would not say anything else, because his daughter’s attorneys told him not to speak to the media.

Around Kent, about 20 miles south of Seattle, people know Earl Norwood and his wife, Larkita, as being polite to the point of formal but say they are a friendly and generous couple who raised nine children to act the same way.

Even in years when their business struggled, the Norwoods forked out thousands of dollars a year to keep their children playing for traveling soccer clubs. “He never complained. He had a couple in the program at a time,” said Brian vanBlommestein, who coached Brittany Norwood at the club.

Earl Norwood always came to the games in slacks, a collared shirt and jacket — never tennis shoes or a T-shirt, vanBlommestein said.

On the field, their youngest daughter was swift, unafraid of the bigger players. “She could knock your fillings out,” vanBlommestein said, but it was never something he saw her carry off the field, where she was mild-mannered and notched good grades.

“I hope to play soccer throughout my college years and someday play on the U.S. Women’s National Team,” she wrote before her senior year, a reasonable goal given her talent, said Brandon Frederick, another coach.

A friend in the class ahead of hers had accepted a soccer scholarship at Stony Brook University in Long Island, N.Y., and Norwood followed the next year, Frederick said. In a school full of New Yorkers, Norwood, who studied sociology, stood out as a cheerful suburban kid who said “hi” and “how are you” as if the phrases demanded exclamation points.

“In the four years I knew Brittany, I never saw her upset, never saw her angry at anyone,” said Glentis Michel, a college friend. “She always had a big smile on her face.”

Her soccer teammates noticed the same, charming nature, but two said they discovered another side as well: Norwood stole cash from them. Leanna Yust, now living in St. Louis, said she and others reported the thefts to their coach, who did not take action. The coach, Sue Ryan, declined to comment.

‘The sunshine amid the storm’

By 2007, Norwood was living in Arlington County, according to court records, apparently having moved to the area in part to be near family members. She landed a job on the front desk at the Willard InterContinental, a luxury hotel on Pennsylvania Avenue near the White House.

She soon displayed enough charm and smarts to earn the assignment of managing VIP guests, co-workers said. When dignitaries and big shots arrived, they would often be greeted by Norwood, who would help them get checked in and settled, the co-workers said.

Behind the scenes, hotel work can be a grind — irritable and jet-lagged guests demanding this and that. But Norwood was always upbeat. “Don’t let them get you down. Don’t be sad,” former Willard colleague Catherine Garrett remembers Norwood telling her.

Norwood was the staff “cheerleader,” Garrett said, “the sunshine amid the storm.”

A Willard spokeswoman confirmed that Norwood worked at the hotel and left “on her own accord,” but the spokeswoman declined to discuss Norwood’s job or performance.

Murray, two years older than Norwood, was also staking out a life in Washington. The daughter of a Houston oil operations manager, she traveled the world as a youngster. She tried the Girl Scouts, her family said, but found it boring. She began tagging along on Boy Scout outings with her two brothers and their father, who was the scoutmaster and a former Army officer.

It was an upbringing that formed a strong sense of right and wrong, said her brother Hugh and father, David, and a sense that there was a line you don’t cross.

She studied marketing in graduate school at Johns Hopkins University, and while there, she noticed a friend’s bag, decked out in sayings from a store with a funny name with no capital letters: lululemon athletica.

She learned more about its grass-roots marketing strategies and wrote a paper about Lululemon, which led to a job at the company’s Bethesda store, her family said.

She fit the bill. Lululemon staffs its stores with outgoing, athletic and ambitious people, who write their life’s goals and display them inside the stores. Their personalities are key to the stores’ success: Employees get discounted apparel, which they’re expected to wear to nearby health clubs and yoga studios. They become walking advertisements, espousing the benefits of Lululemon’s $98 yoga pants and $58 running shirts.

Lululemon Athletica officials declined to answer any questions for this report.

‘We wanted to believe her’

When Montgomery police officers first found Norwood, they thought she might be dead. Shortly after 8 a.m., an employee showed up to open the store and saw trouble. The responding officers saw Norwood tied up on the floor in a restroom, according to court records.

But Norwood was alive; she was taken to a hospital and interviewed by a detective. “Probably our most compassionate one,” a police source said.

Inside the store, detectives and forensic technicians — their shoes covered in protective booties — were trying to make sense of Norwood’s story.

The story didn’t track with some of the things they were seeing, but at least part of that could be attributed to what she said she had been through. Victims of extreme trauma can take three days to recall specific events, said Capt. David Gillespie, head of the department’s major crimes section.

By Tuesday, four days after the killing, detectives had several problems with Norwood’s story: The imbalance of injuries, evidence found in Murray’s car, the odd trace of incomplete shoe prints inside the store that appeared to stop before either exit, according to police charging documents.

But even as Norwood came into clearer focus as a suspect, detectives looked for ways her story could be true: Maybe the man who attacked her simply wasn’t as violent as the one who had attacked Murray; maybe the attackers took off their shoes, put them in a Lululemon bag and walked out in their socks.

“We wanted to believe her,” said a source.

But by not pushing her, they also were employing an investigation tactic of keeping her talking.

“We were more thorough with each subsequent interview,” said Tracy, the assistant police chief. Detectives made logical inquiries, based on her story, he said: Possible weapons? Were assailants right-handed or left-handed? Did they have accents? Did they utter any names? What was Jayna doing during the attack? What was she doing during the attack?

But the pieces weren’t fitting together, he said.

That appeared to pay off when Norwood told detectives she wanted to explain why she might have been in Murray’s car that night. The story she told — that the assailants had told her to go move Murray’s car and return — sealed her fate in the minds of the detectives, according to court records.

On March 18, they charged Norwood with first-degree murder. Since then, they have talked to numerous co-workers and uncovered no personal feud between Norwood and Murray.

That has led them to think that the rage built up over a matter of minutes. Over a petty theft.

Murray suffered so many overlapping wounds that detectives had a difficult time determining the exact murder weapons. At one point, two sources said, detectives delivered a collection of instruments from the store to the state medical examiner’s office in Baltimore to try to match with the autopsy records.

The attack defied logic, one police official said.

Norwood was “very articulate” in interviews with detectives but didn’t always provide specific information, Tracy said. “She was trying to manipulate her story to fit the circumstances of what occurred that Friday.”

There is no indication from court records that detectives were able to coax a full statement from Norwood. At one point, they listened as she spoke to a brother alone in a room after her arrest. He asked her whether she did it, prosecutors said in court.

“I don’t want to disappoint you. I’m sorry,” she said, according to detectives. “I don’t want to talk here.”

Staff researchers Jennifer Jenkins, Magda Jean-Louis and Madonna Lebling contributed to this report.