Destination Inner Space is a 1966 science fiction film produced by Earl Lyon, directed by Francis D. Lyon, written by Arthur C. Pierce, and stars Scott Brady, Gary Merrill, and Sheree North. The film was released to theaters in the US in May 1966 on a double bill with Frozen Alive (1964); its broadcasting rights were pre-sold to television so that some of the licensing fee could be used to finance the film's production. The story centers on scientists working in a laboratory on the floor of the ocean. They encounter an undersea flying saucer, after which the lab is attacked by a colorful aquatic humanoid monster who they fear may be the first in an alien invasion.