Frankenstein Conquers the World

The still-beating heart of Frankenstein's monster was transported from Nazi Germany to Japan for experimentation during World War II. But the heart is believed lost when Allied Forces drop the bomb on Hiroshima. Several years later, a feral boy is running rampant through Hiroshima, killing and feasting on small animals. This causes alarm and arouses the curiosity of an American scientist, Dr. Bowen (Nick Adams), and his assistant (Kumi Mizuno) who take the boy into their care. Soon, the boy is growing at an alarming rate and exhibiting incomparable strength. The scientists only have one explanation: this is the mutated monster of Frankenstein himself! But this town isn't big enough for two monsters. The destructive, underground-dwelling Baragon emerges to do battle with Frankenstein to the death! (official distributor synopsis)