The Incredible Petrified World

John Carradine, whose entire role consists of narrating from a chair and never meeting the rest of the cast, sends four scientists down in a diving bell that snaps its cable and sinks into a subterranean cavern — a glowing "petrified world" where the survivors bicker, pair off, and dodge stock footage until they find a volcanic vent to ride back to the surface. Made by Jerry Warren, one of the true minors of 1950s exploitation, from a script padded out around underwater footage shot in Santa Catalina's real submarine gardens. It is exactly as slow and threadbare as that sounds, which is why it remains a fixture of public domain sci-fi collections and late-night movie marathons. The film is in the public domain.