A thief steals a used notebook computer from a store; a car hits the thief, and two occupants of the car stuff the victim into the back seat; the thief is Amir, the nephew of Yusef, whom Sam still owes on a debt incurred in Afghanistan some years ago; a third occupant of the car, Habib, is a known terrorist; Callen and company investigate (after several tense moments at the start). While Sam visits Yusef, bad guys drive by and open fire; Sam returns fire and drops one of them, Ali, a member of a radical jihadist group; Eric learns that Ali and Amir knew each other; Kensi and Deeks meet Nicole, Amir's girlfriend; Sam follows Ali's brother, then he and G find an arsenal; Kensi and Deeks go back to Nicole's pad, where they find her in trouble, and where they exchange fire with bad guys, rescue Nicole, and see a photograph; Deeks experiences enlightenment; Sam goes back to the boathouse, where he enters a mess; G, Kensi, and Deeks pitch in, then everything works out.

After Callen receives a cryptic message from Hetty, he tracks down the person tailing him, bringing him to a remote location teeming with Russians - and face to face with Anna.