"Watchmen" is set in an alternate 1985 America in which costumed superheroes are part of the fabric of everyday society, and the "Doomsday Clock" -- which charts the USA's tension with the Soviet Union -- is permanently set at five minutes to midnight. When one of his former colleagues is murdered, the masked vigilante Rorschach, washed up but determined, sets out to uncover a plot to kill and discredit all past and present superheroes. As he reconnects with his former crime-fighting legion -- a ragtag group of retired superheroes, only one of whom has true powers -- Rorschach glimpses a wide-ranging and disturbing conspiracy with links to their shared past and catastrophic consequences for the future. Their mission is to watch over humanity... but who is watching the Watchmen?