"Return to Tomorrow" is a second season episode of the original science-fiction television series, Star Trek, first broadcast February 9, 1968, and repeated August 2, 1968. It is episode #49, production #51, written by John T. Dugan, under the pen-name "John Kingsbridge", and directed by Ralph Senensky. In this episode, telepathic aliens take control of Captain Kirk's and First Officer Spock's bodies.