The latest number that the machine dispenses belongs to Michael Cahill, who on the surface is an unassuming and upstanding but solitary citizen, which masks the fact of being involved in a major smuggling ring led by a man named Neil Vargas. Members of the ring will not hesitate to kill if anyone gets in their way. Reese quickly infiltrates the smuggling ring as one of their own. But when Reese follows Cahill away from the group, Reese finds that he is really Daniel Tully, husband, father and undercover cop, who is deep undercover. Tully could have long ago put Vargas away, but is waiting to nab the true ringleader, a man going by the code name L.O.S. Reese also learns that Vargas probably has a connection working inside the police force. While Finch gets Carter to provide information on the police workings of undercover cops, Reese gets Fusco to re-establish his connections with the dirty cops to flush out Vargas' connection inside. If anything goes wrong, it could mean the demise of Tully, Fusco or both. Seeing Tully's conflict of his work against wanting to be with his family, Reese remembers back four years earlier on his return to the US and wanting to at least know what was going on with his ex-girlfriend Jessica.