After a herd of reindeer are mysteriously found dead following a meteor crash in a remote part of Sweden, soldiers and a geologist are called out to investigate. Just as they discover that the meteor is actually a spaceship, a hideous monster destroys their plane and kills the soldier guarding it. As the geologist (along with his figure skater girlfriend) are trying to ski to safety, the monster attacks again and kidnaps the helpless woman. What is this creature, and can it be stopped?

Diane Wilson is found by the police wandering the streets in a state of shock. After medical examiners find nothing wrong with her, Diane goes to northern Sweden to visit her American uncle, geologist Dr. Frederick Wilson. While she is there, reports are received concerning a strange meteor found in the mountains of Lapland. Forbidden to join the expedition with her uncle and his assistant Erik Engström, Diane stows away on the plane. Upon reaching the meteor, they discover that it is actually an alien spaceship surrounded by giant footprints. Erik and Diane go for help, but Diane is captured by space monsters. In an attempt to save her, Dr. Wilson and Erik start an avalanche. Frightened, the monsters release her and take off in the spaceship, narrowly escaping the avalanche.