A distress signal from the Gamma Quadrant reveals Enabran Tain may still yet live. And the search to find him exposes secrets that are about to spell trouble for the Alpha Quadrant.
- Callback: Bashir attempts blood screenings on each of the prisoners to make sure they're not Changelings, but he admits they could very well be useless. The Changeling that replaced Martok successfully beat a blood screening in "The Way of the Warrior". He also points out he can't test the Breen, because the Breen do not have blood.
- The Comically Serious:Garak: Mr. Worf, you're no fun at all!
- Continuity Nod:
- Zig-zagged. Sisko mentions "the recent Borg attack," no doubt a reference to Star Trek: First Contact. However, the stardate of this episode is actually before the film.
- The plan to close the wormhole is based on a technique developed by Lenara Kahn, Jadzia's ex (and the wife/widow of one of her past hosts) from "Rejoined."
- Darkest Hour: The Federation and Klingons are reeling from their recent conflict, with the former also dealing with fallout from the Borg attack. The Cardassian military is in shambles due to Klingon aggression and a civilian government unwilling to return power to the Guls. The Romulans aren't in much better shape, either.Sisko: The Dominion picked a perfect time to invade.
- Famous Last Words:Tain: I was very proud of you...that day...
- Foreshadowing: Dukat assures Ziyal that "Things are going to change on Cardassia."
- God Help Us All: Sisko's reaction to an impending Dominion invasion.
- Godzilla Threshold: Collapsing the wormhole. Nobody wants to do it (especially with Worf and Garak still in the Gamma Quadrant), but it's the best way to stop a Dominion invasion.
- Hope Spot: Using the main deflector to collapse the wormhole. It would've worked, if not for a certain Changeling infiltrator.
- It's All About Me: Dukat concludes that Kira has allowed Ziyal's friendship with Garak because she knows it will anger him. (He also refers to caring for his daughter as a favor to him, and doesn't register Kira's correction that it's about Ziyal.)
- Lost in Transmission: Played with. A great deal is lost in the last message sent by Garak and Worf, but there's enough there (including the final word "imminent"), combined with the loss of their various sensor probes in the Gamma Quadrant, for the crew to realize the Dominion is coming.
- The Mole: The Bashir on the station is actually a Founder.
- Oh, Crap!: Garak and Worf try to sneak through Dominion territory by flying through a nebula, only to find a massive fleet moving out.Garak: [eyes widen in genuine fear] Maybe this wasn't such a good idea after all.
- Papa Wolf: Garak is nearly tossed off the second level of Quark's when Dukat catches him and Ziyal having lunch.
- P.O.V. Cam: The camera cuts to Garak's point of view just as a Jem'hadar soldier slams a rifle into his face.
- Serious Business: Jadzia decides to borrow Worf's favorite operas before he leaves and threatens to lose them if he doesn't return quickly.
- Shout-Out: Kira Title Drops a Star Trek: The Original Series episode when she refers to Dukat's "private little war."
- Take That!: Garak has some strong opinions about a certain kind of tea.Garak: I'd like to get my hands on that fellow Earl Grey and tell him a thing or two about... tea leaves.
- Talk to the Fist: As they're boarded by the Jem'Hadar, Garak politely asks if they could point them in the direction of the wormhole. Their response is to hit him with their rifle butt.
- Villain Decay: Invoked after Dukat confronts Kira over Ziyal's relationship with Garak.Dukat: Save your excuses, Major. You've betrayed me, and I promise you I won't forget it.
Kira: If that is a threat, I'm not impressed.
Dukat: There was a time when Bajorans took Cardassian threats seriously.
Kira: Not anymore.
- Wham Line: Moments before his death, the truth about Tain and Garak comes out.Garak: I'll do as you ask, on one condition...That you don't ask me this favor as a mentor, or a superior officer... but as a father asking his son.
- Wham Shot: Bashir being hauled into the prison barracks. Revealing there's a Changeling spy on the station. Also, note that Bashir is hauled in still wearing his old uniform. The spy has been on the station since just before "Rapture"!
- The sight of a Dominion armada emerging from the wormhole. The invasion has begun.
- You Talk Too Much:Ika'tika: (to Garak) You Cardassians are all alike. You talk too much.