Unknown World is a 1951 independent, science fiction, adventure film, directed by Terry O. Morse and starring Bruce Kellogg, Marilyn Nash, Jim Bannon and Otto Waldis. Although it may have been inspired by Jules Verne's novel Journey to the Center of the Earth (1864), the film was not based on the novel, nor "At the Earth's Core" by Edgar Rice Burroughs, which it just as much resembles.The film was also known as Night Without Stars and To the Center of the Earth.