Detailed first to New Orleans, he worked the basics: drugs, gambling, bank robberies. He tracked down a pilot who had been flying drugs into New Orleans from Tampa. FBI agents met the pilot and arrested him on the tarmac. The pilot looked at Ashooh. “I know you,” he said. They had been in the same karate school. The pilot became one of Ashooh’s first undercover sources. Wired with a recording device, he helped Ashooh bring down a big narcotics network.

“To me, that was what the FBI did,” Ashooh says. “Take down large criminal enterprises.”

From New Orleans, Ashooh went to the FBI’s Newark office. He worked with a team of agents to dismantle a conspiracy in which cops protected drug dealers. “You couldn’t tell the difference between the cops and the wise guys,” he says.

Ashooh had found his calling: using wiretaps and informants to infiltrate old-school organized-crime networks—“Mustache Pete” mobsters, he calls them.

In April 2000, Ashooh got a transfer to the Washington Field Office. He was home, operating from the office his dad had worked in, living with his wife and children in Northern Virginia, working cold cases.

A year and a half later, hijackers crashed passenger jets into the World Trade Towers, the Pentagon, and a field in Pennsylvania. The FBI ordered Ashooh to join the new national calling: ferreting out terrorism networks to make sure the United States wasn’t attacked again.

Ashooh didn’t warm to the task. He had spent nearly two decades working complicated, long-term investigations that usually resulted in putting thugs in jail for more traditional crimes. He discovered that investigating and proving terrorism could take him into uncertain legal terrain.

Youssef called Ashooh in 2004. “Remember me?” he asked. “I said I would call. I have been out of jail for about six months.”

Youssef was a member of a prominent family in Northern Virginia’s Middle Eastern community. He was thought to have connections to politicians and businessmen in the Middle East. After his release, friends had taken him in. Members of the Middle Eastern community in Annandale had loaned him money so he could get back on his feet.

One of his benefactors was Akram Salih, known in the community as a successful contractor. He was born in Puerto Rico but moved with his family to Palestine when he was about four years old. Ten years later, after his parents divorced, he moved to Annandale to live with his father. He attended Annandale High, worked for his father’s remodeling business, and started his own firm, Palis General Contracting. Salih remodeled many old homes on Capitol Hill.

Salih lived with his wife and three children in a tan-brick home on Hirst Drive, off Little River Turnpike.

Amjad Hamed, Salih’s younger brother, lived in the basement. Amjad had grown up in Palestine; he had come to the United States in 1978 as a permanent resident but traveled back and forth to the Middle East. He was in his early thirties. He liked to smoke, drink coffee, and talk about his connections with Fatah, the Palestinian political organization headed by the late Yasir Arafat.

Youssef started spending time with Amjad at the Salih home.

At Ashooh’s first meeting with Youssef, they made a pact. “I am getting to know the Middle Eastern community in this area,” Youssef told him. “Some of my old friends have become radicalized. I want to be your listening post.”

He added, “The younger brother of one of my friends has approached me to do a few things.”

His name was Amjad Hamed.

Youssef and Ashooh would check in with each other about once a month. In the spring of 2006, Youssef left a message: “I think I have something.”

Amjad Hamed had asked Youssef if he could get counterfeit US visas for six of his “associates” who wanted to emigrate from Jordan and the West Bank. He explained that his friends were in danger of being arrested by the Israelis and needed illegal entry to the United States.

Youssef and Amjad had been talking for months about politics and money. They would meet in the parking lot of Pinecrest Plaza on Little River Turnpike in Annandale, not far from Akram Salih’s house. It had a Staples, a Hollywood Video, a Quiznos. The Starbucks was always hopping. Youssef and Amjad would grab a cup, sit in their car in the parking lot, smoke cigarettes, and plot.

When Youssef told Ashooh that Amjad had asked for fake visas, the FBI agent realized it was time to wire up his source. They worked out a routine: They would meet at a pair of blue Dumpsters in an alley near the shopping center. Ashooh would fit Youssef with a device that would both record and beam the conversations to listening devices. Ashooh and other federal agents would watch the meetings and listen to the conversations.

Ashooh also started paying Youssef as if he were a government contractor.

Before Youssef could get the fake visas, Amjad would have to produce passports for the people he wanted to get into the country. For weeks there was much talk but little action. Amjad took Youssef to the basement of his brother’s house and gave him a lie-detector test.

In early April, Amjad called Youssef: “I have what we’ve been talking about.”

On the day Youssef was scheduled to pick up the passports, Ashooh met him at Pinecrest Plaza, wired him up, and gave him last-minute instructions.

Ashooh was a bit woozy. He had gotten a concussion the night before at a karate class.

Youssef waited in the parking lot. Amjad called and asked him to come to the house. He drove down the road and walked into Amjad’s basement apartment. Amjad handed over six Palestinian Authority passports.

“How did you get them?” Youssef asked.

“A passport just as this one has never left the country and was never stamped,” Amjad said. “We got everything organized, and a decision was made. When we got the okay, they sent it to us. I came and found it at the front door.”

Youssef said his source for the fake visas wanted to know if Amjad was serious about the scheme and powerful enough to pull it off.

“As far as being powerful,” Amjad said, “I can bring you the entire universe if you want. Anything you want in the area. If you want him to go to Lebanon to bomb everyone, he will go to Lebanon.”