American astronaut Frank Douglas mysteriously disappears from his spacecraft as it parachutes to Earth. He is apparently replaced by or turned into a large, radioactive, humanoid monster. A team of scientists and military men attempt to capture the monster.

• B.I. & L. Releasing Corp.
• Henry Hite
• Phil Morton
• Lois Brooks
• Rork Stevens
• Robert Simons
• Peter M. Thompson
• June Travis
• George Perry