Gamera vs. Viras

Gamera vs. Viras , Gamera tai uch kaij Bairasu? , Gamera Vs. Space Monster Viras, released in the U.S. as Destroy All Planets is the fourth entry in the Gamera film series.

Later on Earth a Boy Scout troop is visiting an aquarium to the scientists working on a small twoman submarine. Masao and Jim, two of the scouts manage to talk their way aboard the sub. While in the water they spot Gamera who engages in a little race with the boys. However, their hijinks come to an end when the second alien vessel envelops the both of them in a supercatch ray. Releasing the boys, Gamera remains trapped in the force field while the aliens scan his memorywaves. They learn of Gameras one weakness, his soft spot for children. Soon after, the field weakens and Gamera is free. The aliens capture Jim and Masao, threatening to kill the boys. Powerless, Gamera lands. Attaching a brainwave control device to Gameras head, the aliens force the turtle kaiju to do their bidding.While aboard the spaceship, the boys continually try to escape. Gamera, however under the influence of the aliens is destroying dams and cities by the handful. Jim and Masao discover a squidlike creature, thinking he is another captive of the aliens. In fact he is the leader of the aliens. The boys help Gamera break free from the brainwave device, and he begins to attack the spaceship. Grounded by Gamera, the aliens reveal that their human forms were just disguises. The aliens merge to form the giant monster Viras. Gamera and Viras duke it out in a big beachside battle. Gamera manages to pull Viras into the upper atmosphere, freezing him to death. He then flings Virass body back into the ocean. The boys and a crowd of adults celebrate Gameras victory. ........

Source: Wikipedia