Some of Sin City’s most hard-boiled citizens cross paths with a few of its more reviled inhabitants.

Unconscious soldiers are dropped into a testing site only to discover their memories have been wiped and that once docile machines are the new intelligence.

A top Marine sniper, Bob Lee Swagger, leaves the military after a mission goes horribly awry and disappears, living in seclusion. He is coaxed back into service after a high-profile…