24. Empok Nor

Chief O'Brien needs to replace a failing component of Deep Space Nine' s machinery. The only way to obtain a replacement is by salvaging it from Empok Nor, an abandoned Cardassian space station built to the same design as Deep Space Nine. The salvage team consists of O'Brien, Cardassian ex-spy Garak, cadet Nog, engineers Pechetti and Boq'ta, and security officers Stolzoff and Amaro. As Cardassians routinely booby-trap abandoned facilities against non-Cardassian intruders, Garak is brought along to help disarm the security measures, and Garak uses the time to bring up O'Brien and his actions as a soldier on Setlik III against Cardassians.

On the abandoned station, the team discovers two empty and recently deactivated stasis tubes, and a third one with a dead Cardassian soldier, whose uniform marks him as a member of an elite and ruthless battalion. Suddenly, the away team's runabout detaches from the station and explodes, stranding them inside with no means to send for help and under threat from the two recently-awoken Cardassians. The team splits into groups to continue the salvage and attempt to establish communications.

The Cardassian soldiers methodically ambush and eliminate Pechetti and Stolzoff. Garak decides to go on the offensive and track down the enemy soldiers himself. He returns after killing one of them, and relays his discovery that the soldiers had been subjected to psychotropic drugs which amplify their natural xenophobic tendencies. The second soldier ambushes Boq'ta, but Garak emerges and kills him before he can kill Amaro, only to then stab Amaro himself.

O'Brien and Nog discover Amaro, who tells them what happened, before dying from his injuries. O'Brien realizes Garak has been affected by the same drug as the soldiers, and sets out to stop him. Garak captures Nog, using him to draw O'Brien out. O'Brien consents to lay down his weapons and face Garak in hand-to-hand combat, but disables him with his own trap, having rigged his phaser to explode.

The three are rescued after collecting the parts they needed. Back on DS9, O'Brien visits Garak in the infirmary. Garak expresses his sincere regret over his actions; O'Brien informs him there will be an inquest, but it will be made clear that Garak was not responsible for his actions. Garak remarks that he was lucky the phaser did not kill him, but O'Brien admits that he had intended for it to do just that.