The heart of Frankenstein is transported by Nazis to Japan just before the atomic bomb is dropped to end World War II. A hungry child eats the radioactive heart and is transformed into a hideous monster. The monster adjourns to Mount Fugi so no one will see it's horrible visage, battles Baragon, then sets out to destroy Tokyo. Dr. James Bowen Nick Adams is the American scientist who is conveniently on hand to help rebuild the city after the bomb and hopefully stop the giant Frankenstein monster from terrorizing the country.