A joint Federation/Bajoran/Cardassian science mission to establish a communications relay through the wormhole is complicated when a Bajoran vedek believes that success will cause a prophecy of doom to come true.

!!Tropes
* AccidentalMisnaming: The Cardassians are clearly used to the station being called "Terok Nor", leading to a slip of the tongue during a briefing.
* {{Adorkable}}: Ulani and Gilora admit on arrival they'd spent most of the trip to [=DS9=] trying to think of what to say when they go there.
* AnywhereButTheirLips: The Cardassian woman who spent the episode hitting on O'Brien gives him a goodbye kiss on the cheek after he tells her that he's HappilyMarried.
* BrickJoke: Quark intends to welcome the Cardassian delegation with a few bottles of ''kanar'' that he had stashed away, until Dax tells him that it's gone bad. A few scenes later, Bashir mentions Morn coming to the infirmary with food poisoning from a bad glass of ''kanar''. It was on the house, apparently.
* ChickMagnet: ''O'Brien'' thanks to a bit of "[[CrossCulturalKerfluffle Cross-cultural misunderstanding]]."
** {{Tsundere}}: This trope is the way Cardassians flirt.
* CrazyPrepared: Federation standard operating practice includes having a backup to their backup power supplies. Dejar questions this, but given what the average Starfleet ship goes through, it's pretty smart.
* FantasticRacism: Miles thinks this is what's going on, at first. Then it turns out it's not ''humans'' the Cardassian he's arguing with has problems with. It's not even entirely clear if her sexism is real, or just a convenient excuse to trade barbs with him (read: flirt).
* FromACertainPointOfView: The prophecy comes true. Just not in the way Sisko and Kira expected.
* ImADoctorNotAPlaceholder: Ulani and Gilora are scientists, not diplomats.
* TheMole: Dejar is really an Obsidian Order agent, whose mission was to sabotage the project in order to demonstrate that Bajorans and Cardassians could not work together.
* ProphecyTwist: The Bajorans have a prophecy about these events: "When the river wakes, stirred once more to Janir's side, three vipers will return to their nest in the sky. When the vipers try to peer through the temple gates, a sword of stars will appear in the heavens. The temple will burn, and its gates shall be cast open." The Bajorans believe that the "vipers" are the 3 Cardassian scientists, and that their actions will destroy the wormhole. The prophecy actually refers to the 3 comet fragments. When they travel through the wormhole, AppliedPhlebotinum leaks out of the fragments, forming a "subspace filament", which holds the wormhole open slightly, enabling subspace communication with the Gamma Quadrant. The prophecy was completely true, but there was no disaster, it was just misinterpreted.
* SlapSlapKiss: As mentioned, this is SOP for Cardassians. Miles, being [[SeductionProofMarriage Miles]], shuts it down before Stage 3.
* TeethClenchedTeamwork: Despite being their "colleague", Ulani and Gilora don't get along very well with Dejar and often react uncomfortably to her. It's because she's actually an Obsidian Order agent who is there to (without Ulani or Gilora's knowledge) sabotage the mission. When Gilora realizes what Dejar's done, she doesn't hesitate to speak up.
* TokenHeroicOrc: Ulani and Gilora are pretty non-standard Cardassians. Polite, friendly, nervous, fond of foreign food.