Astronaut Tom Trimble and his android double Hermes are deposited at the court of King Arthur after an accident at Nasa leads to the space/time continuum being warped. Tom becomes embroiled in a plot by the villainous Sir Mordred, who is looking to overthrow the king with the help of the wizard Merlin. Disney family adventure based on Mark Twain's A Connecticut Yankee in King Arthur's Court, starring Dennis Dugan, Jim Dale, Kenneth More and Ron Moody