This was the first appearance of Julianna McCarthy on the series. Her character Mila appeared in a greater capacity in "The Dogs of War" and "What You Leave Behind".
This episode marks the appearance of a new style of Tal Shiar uniform. This redesign was Ronald D. Moore's idea. After he watched the episode "Visionary", he came to feel that the old style Romulan uniforms were unacceptable and he had Robert Blackman give the design an overhaul; "I hated, underline hated, the Romulan costumes. Big shoulder pads, the quilting, I just loathed it. I begged, insisted, screamed, pleaded."
The second part of this two-parter, "The Die is Cast", was not the next episode to be shot. Because it was never intended to be a two-parter, pre-production on "Through the Looking Glass" was already well underway when "The Die is Cast" was green-lit. As such, the episodes were shot out of sequence and the airdates of this episode and "Through the Looking Glass" were flipped.
One of the favorite episodes of Ronald D. Moore.
This episode (along with "The Die is Cast") was broadcast by the BBC in a feature-length format on its first airing on 13 March 1997.