In 1982, a research team in Antarctica is terrorized by a shape-shifting alien that can assume the appearance of its victims. As the team members try to figure out who has been infected, paranoia and suspicion consume them. With the threat of the alien organism taking over the world, they must find a way to survive and stop the creature before it's too late.

At an Antarctica research site, graduate student Kate Lloyd and scientist Dr. Sander Halvorson discover an alien craft and bring back an organism encased in ice. As they study and attempt to extract tissue samples from it, they realize that it is an organism capable of replicating any living creature perfectly. The team faces paranoia and mistrust as they try to determine who has been assimilated by the creature and stop it from reaching civilization.