The Littlest Hobo Has a Time Machine

Summary: In which Kira is gaslit on a galactic scale by the Cardassians.

It's their absolute specialty, to be fair. Kidnap the Major, give her incredibly drastic cosmetic surgery (do Bajorans and Cardassians have similar enough biology that... well, they can interbreed... you know what? nevermind) and give her a brand new pile of existential trauma. The reasons for this? Oh, the usual. (Political fuckery with a personal touch.)

"This is absurd. You can mutilate me, change my appearance, you are never going to convince me that I am a Cardassian." -- Bet.

They tell her she's been a brainwashed secret agent assuming the identity of Kira and go to the lengths of planting some Bajorans who recall things about Kira she of course doesn't... and then there's the whole... drastic cosmetic surgery and bringing in an older Cardassian who is very eager to believe Kira is his daughter Iliana.

I think the episode could linger for a few beats on the abject creeping body horror and the hog wild violation this all is, but even so, the torments visited upon Kira, having been made into her nightmare and then treated so convivially and insistently are... I mean, there's no therapy yet designed to cope with all this nonsense. Kira's a survivor though, and a deeply empathetic person, and she does come around to really liking Ghemor, who, after all, is not in any way in on the fix.

The Obsidian Order does all of this to expose Ghemor as a dissident. Or, rather, they weaponize that Iliana Ghemor did indeed go undercover and they grab Kira as a convincing doppelganger. The fate of the 'real' Iliana is a thread followed up on in the 5th season, though iirc, it remains somewhat unclear. What is true is that the original ending of Second Skin had Bashir conclude he actually couldn't definitively rule out if Kira was Kira, which is... somewhat goofy, but kind of funny.

It's also very sad, how Ghemor was so willing to believe. I think that's probably a bigger factor in Kira eventually making a friend of him.

"The Obsidian Order is Cardassia." -- Entek, shortly before Garak gets the drop on him.

And Garak is... the Obsidian Order? Garak serves Cardassia. The order serves Cardassia... he vaporizes Entek but only when the damage has been dealt to Ghemor and Ghemor is alive but exiled. Keeping some options open re: the Obisidian Order vs. Central Command vs. The Detapa Council. That's either Cardassian realpolitik or Garak is pure ego and chaos. Ghemor warns Kira about Garak, but when or how could that possibly help?