This episode, reminiscent of "Spectre of the Gun", is a companion piece to second season's "Necessary Evil," returning us to the dark days when the Cardassians ran Terok Nor (Deep Space Nine) and exploring Odo's past in a roundabout way. The plot goes in circles for a while, coasting on the mystery of the premise, before finding a direction in the second half and turning into a satisfying Odo character piece (making us wonder why Sisko, Garak, and Dax are such a large part of this thing to begin with). Overall, however, it comes across as a poor man's "Necessary Evil", with the same dystopian cinematography and a similar surprise revelation, but without the great plot and story structure of its predecessor.
Worth watching? Yes. A special DS9 episode? No.