Season 1, Episode 15:
"This isn’t just some speech. We’re not... walking in the dark. We are the dark."Reese and Finch work to protect Michael Cahill — real name Daniel Tully — a narcotics officer working undercover in a smuggling ring. He's trying to arrest "L.O.S.", the head of a major drug smuggling operation, and Reese goes undercover in the gang as well to keep Tully's cover intact. When Reese and Finch learn that the smugglers have paid off HR to expose the undercover cop in their operation, Fusco breaks into a secure part of police headquarters and destroys the file that would've exposed Tully before being caught by HR's officer on the inside. Reese frames himself as the undercover cop and Tully pretends to kill him, giving Reese a chance to slip away and call for backup. With Carter's help, he and Tully apprehend the smuggling gang and L.O.S., who is really a CIA officer selling drugs on the company's behalf to fund The War on Terror. Fusco is driven to a remote location so that HR's officer can kill him, but Reese intervenes at the last moment and kills the officer. He orders Fusco to ask for HR's help in covering up the murder, giving Fusco a way to infiltrate HR. L.O.S. is bailed out of prison by Mark Snow, only to be killed in the back of an SUV as punishment for being caught.In flashbacks to 2008, Reese, Stanton and Snow are on assignment in a "god-forsaken place" where they're not sanctioned to operate: New York. Their job is to extract a government official who tries to sell "software" to the Chinese, but it's another twelve hours before their extraction arrives so Snow orders Reese to get some R&R. He goes down to the bar and strikes up a friendly conversation with Peter, seemingly a random patron, but when Stanton arrives she recognizes Peter as the new husband of Jessica, Reese's ex-lover. She convinces him to let the past go and they leave before Peter can "introduce" the pair to Jessica.
— Kara Stanton
Tropes present in this episode include