The Thing is about a group of researchers in the Antarctic who are threatened by an alien that can change its shape to imitate any life-form it kills. It is a science-fiction horror film directed by John Carpenter and includes a varied cast of known actors. The initial conflict is preceded by unknown circumstances involving a different research base.
The chain of events that would lead to this inevitable collision with such a destructive force begins with a dog being chased into the researchers camp by a helicopter and its rifleman. After being forced to kill the rifleman in defense, they kennel the animal and locate the base that the helicopter came from. Among the corpses they find is a disfigured human-like creature with two faces. They bring the corpse to their own camp to examine and during this process the dog they kenneled along with their sled dogs, metamorphoses and attempts to kill the other dogs.
After conducting the autopsy on the alien, Blair, played by Wilford Brimley, realizes the potential threat it poses to civilization. Upon concluding that anyone can become the creature, he begins to isolate himself from the remaining group. Following an encounter with one of the other group metamorphosing, Blair begins to sabotage equipment supposedly to prevent the creature from reaching larger populations.
Kurt Russell's character, MacReady, insists on a blood test that would determine who the alien is. This forces the creature out into the open and is immediately killed alongside one of the other group members by MacReady. Believing there is still another person the alien had assimilated, the fellow researchers come to realize that Blair has also been copied and destroy the base leaving only MacReady and Childs to endure the cold and the wait.