King Dinosaur is a 1955 American science fiction film starring William Bryant and Wanda Curtis with narration by Marvin Miller.

Five years in the future (1960), four scientists (zoologist Dr. Richard Gordon, geologist Dr. Nora Pierce, medical specialist Dr. Ralph Martin, and chemist Dr. Patrica Bennett) are selected as astronauts to travel to an ancient planet called Nova that has just entered Earth's Solar System.

After first discovering normal Earth animals such as a kinkajou which they refer to as a lemur, crows which they call vultures, and an alligator (A Prehistoric species called Diplocynodon), they soon encounter and battle giant insects, an enormous snake known as Gigantophis, and prehistoric mammals like a Cave Bear, a Mastodon, and a Glyptodont.

Richard and Nora paddle a raft out to an island and are trapped in a cave by Prehistoric Reptiles, even a Tyrannosaurus rex (portrayed by a green iguana).

Back on the mainland near their spaceship, Ralph and Patricia see the distress signal, grab the auxiliary nuclear power supply and paddle their raft out to the island to rescue Richard and Nora.