"The Lisa good news," she'd said, referring to Terry's South African code name.

Now the whole Squillacote and Stand family sat down at a table with Robert, the secret agent. The Sun Dial Lounge revolved slowly, and they could see, in the distance, the CNN Center and the Georgia Dome. While the kids sipped their Shirley Temples and Huck Finns, Robert brandished several three-by-five cards. Terry signed her name "Patricia A. Cunningham," and Kurt signed his "Harold T. Harding." Finally, when everything was in order, they looked out the window and watched the world spin beneath them.

It was around this time that someone slipped a note under Jim Clark's door. He'd been out after work and almost stepped on it when he came home. Scribbled in almost illegible black ink, it told him to be at the Best Western hotel at 20:00 hours and wear a baseball cap. It was signed, "Keep the faith, Your Friend."

Uncertain what to do, he drove past the hotel, then came home before anyone could see him. As he entered the apartment, the phone rang. He picked it up, and a man with a Russian accent told him to meet at the lobby of the hotel. It's about Harry, he said, then hung up.

Terrified, Jim climbed back in his car and returned to the Best Western for the second time that evening. It was just before midnight when he walked into the lobby, his hat pushed down over his forehead. "You don't have to wear the cap now," a man said, standing in the center of the room. Jim removed his cap and the man led him up to his room.

"Sit down," he said, pointing to the bed. "I have a greeting from Harry.... My people in Moscow work with him. I'm from Russian Embassy."

Jim didn't say anything. Maybe the room was bugged.

"One of my people was supposed to make contact with you," he continued. "You remember that?"

Jim had tried through Harry to establish contact with the KGB a few years before. "No," he said, lying just in case.

"Harry," the man went on, "had a little trouble with authorities in Germany."

Jim turned white. The man said Harry was fine, but they suspected that someone in their unit was fingering them one by one. Then he dropped the bombshell: the couple, his friends, may no longer be reliable. He insisted that they were safe as long as nobody did anything dumb. "But if somebody starts to ... how you say? Blabber the mouth or something." His voice trailed off, as if to let the prospect sink in.

"No one else knows," Jim assured him.

The man took out a bottle of scotch and offered Jim a drink. "You understand that the trust thing is still just partial with me," Jim said, raising his glass.

Of course, the man said, and they both clinked glasses and poured down their scotch.

Over the next few nights, they met secretly. But, just as Jim was starting to feel more secure, Terry called. She had seen another article, this one suggesting that Harry had been arrested. As the two of them huddled together at a crowded pub on Twelfth Street—Kurt was away on business--Jim finally told her about the Russian. After a while, they both became convinced he was an undercover FBI agent. How else did he know so much? Terry lit a cigarette and let the smoke curl around her mouth. Jim had just "slit" all of their throats.

She raced home and called Kurt, then typed a letter to her South African handler, warning him that they had all been substantially compromised. "I would like to try to find a way to get out and live a productive life elsewhere," she wrote, "where I could continue to make a contribution." In a separate missive, she said she no longer trusted Jim. He seems to think "Ross Perot is a progressive direction for activists."

Jim, meanwhile, no longer trusted anyone. He made a copy of the federal statute against espionage and studied it for hours. "You're so fucked," he told himself.

When Kurt returned, he tried to calm them both down. "[T]hey're throwing this out to see if anybody pops up," he said. "And then they can ... catch them."

But, a few days later, a woman with a German accent called Terry and said: "This is your friend's daughter. I have message from my father.... Can I read it to you?"

Yes, Terry said, her heart racing. "Your friend is in trouble. He is being closely watched."

The woman asked if Terry understood, then the line went dead.

Now they all began to panic. "I gotta get outta here," Jim said. At his apartment he ripped apart his books and journals, shredding any evidence. "Vernichten," he said in German. "Destroy! Destroy!" He stuffed his belongings in plastic bags and dragged them across the floor. "I'm going far away—Tibet!"

But, before he could even get downstairs, the Russian called and left a message on his machine saying they had to meet. "Get lost!" Jim screamed at the machine. "I don't wanna fuckin' see you again!" He took out his passport and stash of money. He knew a place in Mexico, an abandoned building near the border where he could hide. But, instead of leaving, he started to sob. "I'm not very good at this," he said. He opened the window and stuck out his head. "My God," he muttered, "my parents."

He bent over and started to hyperventilate. Don't lose control, he told himself. Don't lose control. "I know nothing," he shouted. "I know nothing."

On his way outside, a dozen FBI agents surrounded him. A few hours later, Terry and Kurt tried to make it to a hotel in Virginia to meet with Robert. But, as they exited the elevator, a second team of FBI agents enveloped them. In the ensuing chaos, Terry noticed Robert standing with the other agents, and it suddenly dawned on her: he was FBI, just like the Russian and the German woman who had called claiming to be Harry's daughter.

The spy lives in his own moral universe. He lives in a place where there is little light or intimacy, where, as John Le Carre once wrote, people "have seen too much and suppressed too much and compromised too much and in the end tasted too little." Ultimately, he can trust no one—for, deep down, he knows that a person who can betray his country can betray anything or anyone. "The difference between intelligence officers and other people," explains the spymaster Hoffman, "is that we anticipate—and, over time, expect—lies and faithlessness. Every relationship carries a stain of suspicion."

At the trial, it became clear the degree to which every character had betrayed someone for something. Robert, the undercover FBI agent, had betrayed Terry for his country. Terry had betrayed her country and husband for Harry. Harry, who went to jail briefly in Germany and was now a real estate agent in Berlin, had betrayed Kurt for Terry. (Kurt learned about his wife's infidelity for the first time in the newspaper after their arrest.)

Meanwhile, Kurt's lawyer, Richard Sauber, left open the possibility that Kurt might turn against his wife to exculpate himself. "A man in Mr. Stand's position ... has a terrible Hobson's choice," Sauber told the judge. "If he testifies to his own minor role ... he places himself in the impossible position of pointing the finger at his spouse." Though in the end Kurt could not betray the only woman he had ever loved, there was still one last act of betrayal: in exchange for a shorter sentence, Jim pled guilty and testified against Kurt and Terry. Afterward, when the prosecution asked Jim if he still considered Kurt and Terry his friends, he looked at them plaintively and said, "Yes."

The trial lasted nearly a month. Kurt and Terry were charged with conspiracy to commit espionage, attempted espionage, and illegally obtaining national defense information. Two of the city's best defense attorneys took the case almost entirely pro bono because they believed their clients had been entrapped. Terry's lawyer, Larry Robbins, and Sauber revealed how the FBI had found their clients' names in the Stasi files, then tapped their phones for more than a year, found Terry's letter to the South Africans in a search of her home, and set up an elaborate sting with Robert and the Russian undercover agent. They argued that, unlike Jim, their clients had never turned over any classified documents until after the sting. And, as the spectators stared in bewilderment and Terry sank in her chair, they noticed that even the information passed on during the sting had already largely appeared in The New York Times and Jane's Defense Weekly.

Oddly, the prosecution mostly shied away from the defendants' archaic ideology. It emphasized money as their primary motive, even though they had received relatively little. Venality, it seemed, was easier for the jury to judge than idolatry.

The defense, in turn, chose the only explanation that seemed plausible for Terry's strange behavior during the sting: she must be nuts. The defense cited the FBI's own internal psychiatric report, which the agency used in designing its undercover operation and which stated that Terry suffered from "cramps and depression"—and would likely try to kill herself after being caught. But, when the jury looked at all three defendants, it saw only one thing: Benedict Arnold.

Jim was sentenced to twelve years in prison. Kurt and Terry received 17 and 21 years, respectively. In a note to the judge, Jim wrote that he had spied "entirely for ideological reasons.... I have always been dedicated to a political movement that is opposed to greed and selfishness." In a separate letter, Kurt maintained his innocence. Terry, meanwhile, pleaded futilely for mercy. "This is the last gasp of the Old Left," said one of their friends in the Old Left as they departed the courtroom.

When I finally met Terry and Kurt, they were waiting to be transferred from the local Alexandria jail to a federal prison. Kurt came down to a visitors' room. He sat behind a Plexiglas window and talked through a phone. He had lost weight, and his uniform hung too loosely over his shoulders. His kids had gone to live with his brother in the Bronx, and he barely saw them. "They have a right to be upset and angry" with us, he said. "They have a right to have Mother and Father home with them."

When I went downstairs to see Terry, she had just been moved to the psychiatric floor. Her face was puffy, and her hair stood almost on end. After only a few minutes, a guard handed her two pills and a glass of water. "Time's up," he said. Before she left, I asked her the only thing I still didn't know: Had she lost faith in her beliefs? She looked at me oddly and pushed her face close to the glass so that I could see her veins. "No," she said. Just the opposite. In jail, she said, she had finally found a place where the state "took care of all the broken people of the world."

David Grann is an American journalist and best-selling author. He has written about a range of subjects, from New York City's antiquated water supply system to the hunt for giant squid to the U.S. presidential campaign.

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