Howard Gilbert aspired to be a CIA agent but lacked pertinent experience. So to pad his résumé, he hatched a plan to infiltrate a mosque in the suburb of Pembroke Pines by posing as a Muslim convert named Saif Allah . He told congregants that he was a former Marine and a security expert, and one night in late 2000, he gave a speech about the plight of Palestinians.
"That was truly the night that launched me into the terrorist umbrella of South Florida," Gilbert would later brag  to the South Florida Sun-Sentinel.
Nineteen-year-old congregant Imran Mandhai, stirred by the oration, approached Gilbert and asked if he could provide him weapons and training. Gilbert, who had been providing information to the FBI, contacted his handlers and asked for more money to work on the case. (He later claimed that the bureau had paid him $6,000.) But he ultimately couldn't deliver—the target had sensed something fishy about his new friend.
The bureau also brought in Elie Assaad , a seasoned informant originally from Lebanon. He told Mandhai that he was an associate of Osama bin Laden tasked with establishing a training camp in the United States. Gilbert suggested attacking electrical substations in South Florida, and Assaad offered to provide a weapon. FBI agents then arrested Mandhai; he pleaded guilty in federal court and was sentenced to nearly 14 years in prison. It was a model of what would become the bureau's primary counterterrorism M.O.—identifying a target, offering a plot, and then pouncing.
Gilbert himself didn't get to bask in his glory; he never worked for the FBI again and died in 2004. Assaad, for his part, ran into some trouble when his pregnant wife called 911. She said Assaad had beaten and choked her to the point that she became afraid  for her unborn baby; he was arrested, but in the end his wife refused to press charges.
The jail stint didn't keep Assaad from working for the FBI on what would turn out to be perhaps the most high-profile terrorism bust of the post-9/11 era. In 2005, the bureau got a tip  from an informant about a group of alleged terrorists in Miami's Liberty City neighborhood. The targets were seven men —some African American, others Haitian—who called themselves the "Seas of David"  and ascribed to religious beliefs that blended Judaism, Christianity, and Islam. The men were martial-arts enthusiasts who operated out of a dilapidated warehouse, where they also taught classes for local kids. The Seas of David's leader was Narseal Batiste , the son of a Louisiana preacher, father of four, and a former Guardian Angel.
In response to the informant's tip, the FBI had him wear a wire during meetings with the men, but he wasn't able to engage them in conversations about terrorist plots. So he introduced the group to Assaad, now playing an Al Qaeda operative. At the informant's request, Batiste took photographs of the FBI office in North Miami Beach and was caught on tape discussing a notion to bomb the Sears Tower in Chicago. Assaad led Batiste, and later the other men, in swearing an oath to Al Qaeda, though the ceremony (recorded and entered into evidence at trial) bore a certain "Who's on First?" flavor:
"God's pledge is upon me, and so is his compact," Assaad said as he and Batiste sat in his car. "Repeat after me."
"Okay. Allah's pledge is upon you."
"No, you have to repeat exactly. God's pledge is upon me, and so is his compact. You have to repeat."