A test pilot is missing and a search party is sent out in the jungles of Mexico; however, while searching they uncover a monster in the jungle who became this way due to a dose of radioactivity.
James Craig
as Russ Bradford
Gloria Talbott
as Susan Winter
Lon Chaney Jr.
as Martin 'Marty' Melville
Tom Drake
as Lee Brand
Duncan 'Dean' Parkin
as The Cyclops
Vicente Padula
as The Governor
Marlene Kloss
as The Salesgirl
Manuel López
as The Policeman
