There’s two Julian Bashirs. One is the real one, and the other is a changeling. They’re standing side-by-side, look identical, act identical, and sound identical. The crew has to decipher who’s who.

Sisko and Kira begin with a series of medical questions.

Dax and O’Brien cut in with personal questions.

Odo and Worf watch the facial expressions and responses for each.

And then Garak comes in, shoots them both a low-setting phaser shot, and then promptly gets arrested. But hey, the mystery’s solved, as one Bashir’s unconscious and the other has morphed into changeling goo.