In Washington, D.C., and its suburbs, December 2, 2001, was fine but cool, the start of the slide into winter after a spell of unseasonable warmth. At 10 o’clock that morning, Sibel and Matthew Edmonds were still in their pajamas, sipping coffee in the kitchen of their waterfront town house in Alexandria, Virginia, and looking forward to a well-deserved lazy Sunday.

Since mid-September, nine days after the 9/11 attacks, Sibel had been exploiting her fluency in Turkish, Farsi, and Azerbaijani as a translator at the F.B.I. It was arduous, demanding work, and Edmonds—who had two bachelor’s degrees, was about to begin studying for a master’s, and had plans for a doctorate—could have been considered overqualified. But as a naturalized Turkish-American, she saw the job as her patriotic duty.

The Edmondses’ thoughts were turning to brunch when Matthew answered the telephone. The caller was a woman he barely knew—Melek Can Dickerson, who worked with Sibel at the F.B.I. “I’m in the area with my husband and I’d love you to meet him,” Dickerson said. “Is it O.K. if we come by?” Taken by surprise, Sibel and Matthew hurried to shower and dress. Their guests arrived 30 minutes later. Matthew, a big man with a fuzz of gray beard, who at 60 was nearly twice the age of his petite, vivacious wife, showed them into the kitchen. They sat at a round, faux-marble table while Sibel brewed tea.

Melek’s husband, Douglas, a U.S. Air Force major who had spent several years as a military attaché in the Turkish capital of Ankara, did most of the talking, Matthew recalls. “He was pretty outspoken, pretty outgoing—about meeting his wife in Turkey, and about his job. He was in weapons procurement.” Like Matthew, he was older than his wife, who had been born about a year before Sibel.

According to Sibel, Douglas asked if she and Matthew were involved with the local Turkish community, and whether they were members of two of its organized groups—the American-Turkish Council (A.T.C.) and the Assembly of Turkish American Associations (A.T.A.A.). “He said the A.T.C. was a good organization to belong to,” Matthew says. “It could help to ensure that we could retire early and live well, which was just what he and his wife planned to do. I said I was aware of the organization, but I thought you had to be in a relevant business in order to join.

“Then he pointed at Sibel and said, ‘All you have to do is tell them who you work for and what you do and you will get in very quickly.’” Matthew could see that his wife was far from comfortable: “She tried to change the conversation to the weather and suchlike.” But the Dickersons, says Matthew, steered it back to what they called their “network of high-level friends.” Some, they said, worked at the Turkish Embassy in Washington. “They said they even went shopping weekly for [one of them] at a Mediterranean market,” Matthew says. “They used to take him special Turkish bread.”

Before long, the Dickersons left. At the time, Matthew says, he found it “a strange conversation for the first time you meet a couple. Why would someone I’d never met say such things?”

Only Sibel knew just how strange. A large part of her work at the F.B.I. involved listening to the wiretapped conversations of people who were targets of counter-intelligence investigations. As she would later tell investigators from the Justice Department’s Office of the Inspector General (O.I.G.) and the U.S. Congress, some of those targets were Turkish officials the Dickersons had described as high-level friends. In Sibel’s view, the Dickersons had asked the Edmondses to befriend F.B.I. suspects. (In August 2002, Melek Can Dickerson called Sibel’s allegations “preposterous, ludicrous and slanderous.”)