Peering Into Distorted Mirrors

The first time I encountered the idea of parallel worlds — where you might encounter familiar faces existing in an altered reality — was the classic Star Trek episode “Mirror, Mirror,” written by Jerome Bixby. The episode imagines Kirk, McCoy, Scotty, and Uhura entering an alternate version of their world where a totalitarian Imperial Earth controls the galaxy instead of a benevolent Federation of Planets. Crewmembers move up in rank by assassinating superior officers and starships are sent to d...