An artist's rendering of the U.S.S Enterprise destroying asteroids.  Fantasy you say?  Not to Captain Kirk and crew.

Screen shot from the Star Trek episode, "The City on the Edge of Forever."  Here, Captain Kirk and crew stand before the Guardian of Forever, an entity whose job it is to provide travels through time (realities?)

Screen shot from Star Trek IV: The Voyage Home.  Where earlier Captain Kirk and crew were traveling through space destroying asteroids, here, in 1986 San Francisco, they are suddenly subjugated to all the hells of our time--crossing a street without being hit by a car.  If Captain Kirk and crew have trouble with their reality, is it so strange we have trouble with our own?