Frankenstein Conquers the World

During WWII, a human heart taken from a certain lab in Europe (Dr. Frankenstein's) is kept in a Japanese lab, when it gets exposed to the radiation of the bombing of Hiroshima. The heart grows in size, mutates and sprouts appendages, and eventually grows into a complete body and escapes. He grows at an enormous rate and eventually escapes his chains by chewing off his hand, which survives and crawls around until it dies of malnutrition. Frankenstein (as Bowen and Togami choose to call him) is blamed for destruction of the countryside near Mount Fuji, but Akira Takarada swears he saw another monster at the scene of the disaster.(imdb)