A hibernating species of giant carnivorous bird is awakened on a Japanese island. The hideous flying reptiles, the Gyaos, attack a nearby island and the Japanese military encounters an unidentified mass moving beneath the water off-shore. The unidentified mass rises from the sea and it is Gamera. The fire-breathing turtle combats both a misguided military and the man-eating Gyaos, with help from a courageous naval officer, an intrepid ornithologist and a beautiful young psychic.