Dr. Abner Perry is an English scientist who has invented a massive drill that can dig deep into the earth. Joined by his adventure-seeking American backer, David Innes, Perry accidentally discovers an underground civilization of primitive humans who live in fear of telepathic flying monsters. David becomes intrigued by the beautiful native Dia, and must rescue her when she is chosen as a human sacrifice.

• At the Earths Core
• Kevin Connor
• Doug McClure
• Peter Cushing
• Caroline Munro
• American International Pictures (AIP)
• Amicus Productions
• Burroughs Productions Inc