Mirror universe

Alternate universe where Earth ran a brutal empire instead of a benevolent Federation, first seen in TOS and visited in several comic book stories and novels. These stories include Fragile Glass, a one-shot story by Marvel Paramount Comics, The Mirror Universe Saga, an eight-part graphic novel by DC Comics, Dark Mirror, a novel Diane Duane wrote before DS9 aired the mirror-universe episodes, a trilogy written by William Shatner and Judith and Garfield Reeves-Stevens, and Dark Passions, a two-parter written by Susan Wright. Michael Jan Friedman featured people from the MU in Stargazer: Three.