Gamera vs. Zigra

Without warning, an alien spaceship attacks a Japanese moon base. Back on Earth, young Kenichi Ishikawa; his father, Dr. Yosuke Ishikawa; his friend Helen; and her father, Dr. Tom Wallace, witness the spaceship descending into the ocean. They go to investigate but are soon captured by a teleportation beam that brings them aboard the spaceship. Inside the spaceship, a human-looking woman appears to them and reveals that she is of a race called Zigra. She then tells her prisoners of Zigra's history, and its great scientific advances Zigran's overlord is a strange, shark-like being, but the great Zigra tells her that humans must be preserved so they can be used for food. Gamera, intent on discovering the identity of the alien invader, can Gamera rescues the children and their fathers to save the world.