The episode opens in Quark's Bar that seems strangely not to be very crowded. We quickly understand the reason when hearing a horrible sound. It is actually Miles O'Brien and Nog doing some conduit repairs. However, the repairs are heavy and O'Brien soon realize he will need an entirely new plasma distribution manifold. Worse, they are of Cardassian making and cannot be replicated. It is then decided to go scavenge manifolds from the abandoned station of Empok Nor. Because of the Cardassian way of planting booby traps everywhere when they leave a place, a Cardassian expert joins the mission to play as the minesweeper: Garak. The rest of the crew comprises O'Brien, Nog and 4 other starfleet crewmembers: Pechetti, Boq'ta, Stolzoff and Amaro.
They soon arrive at Empok Nor. After Garak disarming the airlock booby trap and restoring emergency power to the station, O'Brien quickly dispatch his teams for the salvage operation. Nevertheless, tension slowly begin to build when we see that there were Cardassians left on the station who woke up from their stasis tubes with the emergency power restored.
A little after, Garak and Boq'ta find the stasis tubes partly filled with an unknown blue substance. Regarding the discovery, Garak contacts the O'Brien team. After Nog witnesses the destruction of the runabout, they conclude that the former occupants of the cells are loose on the station with unfriendly intentions. When a dampening field hindering subspace communication is suddenly activated, they understand that their new priority is to contact DS9 for evacuation. It is decided to use the deflector grid to send a series of covariant pulses. For efficiency, they split again into 3 teams.
The first team, composed of Stolzoff and Pechetti, has no luck and is easily disposed of by the veteran of the Cardassian First Order, Third Battalion. When O'Brien arrives on the death scene, he realizes they had the time to do a pretty complete job. The remaining members split again, even if everyone is beginning to feel clearly insecure. Garak is beginning to act strangely, insisting on going after the Cardassian and inviting the hero of Setlik III (O'Brien) to join his fight.
Garak succeeds in disabling a Cardassian. After running an analysis on the body, he learns that the soldier had been given a massive dose of a psychotropic drug that looks as a failed experiment to develop a stimulant to Cardassians' xenophobic tendencies. He informs O'Brien of his discovery, but his strange behavior (probably from his contact with biogenic substance), causes O'Brien to observe that Garak doesn't have the face of a tailor anymore.
The tailor goes on with his task, killing the second guard, but not being able to prevent the death of Boq'ta. Garak finally loses control to the drug and stabs Amaro with a flux coupler. Insane, he begin playing with the remaining O'Brien and Nog. At this moment, O'Brien decides that securing the place is a greater priority than sending the signal. A cat and mouse game follows. Garak kidnaps Nog, using him to bring O'Brien to him. He arranges a hand to hand duel as it will be more enjoyable to kill O'Brien slowly. Partly blinded by the drug, the Chief easily incapacitates him using a tricorder-phaser bomb.