The Dominion is sending new reinforcements through the wormhole on a weekly basis. Letting them enter puts the whole Alpha Quadrant at risk, which is why Sisko decides to mine the entry to the wormhole, so that no new Jem'Hadar ships can get through. Weyoun warns Sisko that the Dominion will not let them go through with this plan, and a war between the Federation and the Dominion looks inevitable. Sisko uses his leveraqe as the Emissary and convinces the Bajoran government to sign a non-aggression treaty with the Dominion, as this is the only way Bajor will avoid the upcoming war. The B plot of the episode involves Leeta and Rom preparing for their wedding. The forthcoming Dominion attack forces them to have the wedding ahead of schedule, and any chance of marital bliss they might have had is cut short, as all Bajorans are evacuated from the station. The sole exception to this is Kira, who willingly stays on Deep Space Nine, as do Odo, Quark, and Rom.
- Big Badass Battle Sequence: An appropriate way to start a war.
- Breaking the Fellowship: The main characters are separated into two groups: those who are forced to leave Deep Space Nine (Captain Sisko, Dax, Worf, O'Brien, Bashir, Nog, Garak), and those who stay behind on the station (Kira, Odo, Quark, Rom, Jake Sisko).
- Call Back: Garak recalls the time he and Dukat fought side-by-side against the Klingons and how, for a moment, he considered shooting Dukat In the Back.
- Gunship Rescue: Who says there's never a Klingon around when you need one?
- Loophole Abuse: Dukat tries getting around the non-aggression pact by stating it was signed by the Dominion, not Cardassia. Weyoun quickly yanks the leash a little by reminding him Cardassia is part of the Dominion now. And Bajor is off limits.
- Nothing Is the Same Anymore: After three seasons of anticipation, the Federation is now officially at war with the Dominion. Bajor is forced to sign a non-aggression treaty with them, and Federation troops withdraw from Deep Space Nine. At the end of the episode, the Cardassian/Dominion army boards the space station, and it once again becomes Terok Nor, lead by Gul Dukat.
- OOC Is Serious Business: When Weyoun arrives to try and get the minefield taken down, he's dead serious. No fake smiles or compliments. Just a straight threat.
- Pyrrhic Victory: Gul Dukat successfully retakes the station, but fails to stop the minefield from being activated while a Dominion shipyard is destroyed elsewhere.
- Salt the Earth: Kira executes Sisko's program to disable the station once Starfleet has left.
- Scotty Time: Dax and O'Brien repeatedly say they need more time to lay the minefield. Naturally, they get the job done.