The United Planets Cruiser C-57D is a fictional starship featured in MGM's 1956 science fiction film Forbidden Planet. The design used for the starship is a flying saucer, inspired by the spate of UFO sightings during the 1950s, and which itself inspired the look of the exterior saucer section and interior design of another iconic starship, Star Trek's USS Enterprise, as well as the Jupiter 2 space craft from the original 1965 TV series Lost in Space.