What a conclusion. Up to this point, Star Trek has mostly been fumbling with the second halves of the two-part episodes, but this one manages to be satisfying in every way. The shock of Cardassia joining the Dominion is a brilliant moment, prophecised nicely back in 'Rapture' with Sisko's vision of the locusts. It's almost sad to see how Gul Dukat can't understand how he and his planet are being used.
The prison break stuff might be my favourite parts of the episode, though. Worf gets to be extremely Klingon and manages to gain the respect of a Jem'Hadar, which is no small feat. I love that he keeps getting back up even though he's clearly not in any fit state, and that he really can't shrug off the injuries he's sustaining. Meanwhile, Garak gets to shine too when we find out that he's claustrophobic - in his case, he manages to gain the respect of the Klingons, who again are a pretty tough crowd to please.
If the episode feels weak in any areas, it might be the conclusion of the Bashir-Changeling situation. He's going to blow up Bajor's sun by just flying there and sacrificing himself, in the process wiping out significant Federation, Klingon and Romulan fleets. It's a sneaky and very clever tactic by the Dominion that would have worked, but it's execution on screen is a little hard to take seriously. Maybe if Bashir-Changeling had some more dialogue or realisation about how his plan had failed it would have worked better. I'm a bit curious as to why going to warp inside a solar system is a no-no, too.
Nice to see the Klingons finally back on our side. They just feel better as allies.
And so the ball starts rolling...