First of a trilogy of films. During the Second World War, a Japanese conscientious objector named Kaji works as a supervisor in a Manchurian prison camp. He hopes to avoid duty as a soldier, but he also hopes to be helpful to the welfare of his prisoners. An escape attempt by Chinese prisoners results in Kaji's arrest for collusion. He faces the possibility of transferral to combat--or worse.

In remote Antarctica, a group of American research scientists are disturbed at their base camp by a helicopter shooting at a sled dog. When they take in the dog, it brutally attacks both human beings and canines in the camp and they discover that the beast can assume the shape of its victims. A resourceful helicopter pilot (Kurt Russell) and the camp doctor (Richard Dysart) lead the camp crew in a desperate, gory battle against the vicious creature before it picks them all off, one by one.