SPOILER WARNING!!! This post spoils movie The Thing (1982). DISCLAIMER!!! I am not a biologist. I might get something wrong on that area.
Movie starts with Norwegians hunting dog from helicopter. Dog manages to get American science camp. One norwegian kills himself with grenade by mistake and other tries to warn Americans. I assume Norwegians were scientists. It is strange that they didn’t speak english. Other norwegian starts shooting the dog and americans because they are on the way. Americans kill norwegian because they think he has lost his mind. For some strange reason they let the dog wander around science camp. Like they don’t care about their scientific experiments.
Americans go to Norwegian camp where they found burned corpses, frozen corpses and one strange corpse with two head. What happened in Norwegian camp was what happened in The Thing from Another World with exception that Norwegians didn’t win. I have understood that new The Thing is prequel to this movie and tells what happened in Norwegian camp. I haven’t seen that and it is not available at the moment. So I can’t tell anything more about that.
Americans study what they found from Norwegian camp. Finally they put the dog with other dogs. When dog is left with other dogs it turns to nightmarish monster and starts to infect other dogs. Americans, which I stop calling Americans from now on, kill monster. Blair, the main scientist, finds out that the thing infects other species and start to imitate them. If it is left to civilization whole planet would eventually be infected. Men don’t know who is human and who is imitation. Blair kills rest of the dogs and destroys their radio, tractor and helicopter. Men are cut from rest of the world. Others think Blair lost his mind and lock him away.
Men don’t trust each other and the thing kill them and infect them one by one. After they figure out who is human and who is not they go to check Blair. They left Childs alone to main building. They find that Blair has escaped and that Blair is imitation. Question here is was Blair human or imitation when he destroyed their transports and radio. I think he was still human. It don’t make much sense for the thing to destroy ways to escape to civilization. The thing could have infected everyone one by one and then move to next camp. But one open question is had it done that already. Men could not contact any one via radio during the movie. Dog came from norwegian camp and norwegian had found flying saucer. But something had happened to other camps too.
They see Childs running from main building and someone destroying generator. Blair has been building flying saucer. Men destroy it. They decide to burn down everything because they are going to die anyway and they don’t want the thing to survive. After burning everything and killing Blair imitation only two guys survive. Mac who is the hero of the movie and Childs. We know that Mac is still human but we can’t be sure about Childs. Childs were left alone and he might be infected. Movie leaves Childs and Mac waiting for freezing death. If Childs is imitation he will survive until rescuers come.
We did see that imitations can talk. They were like real humans until they were discovered. This makes the thing quite capable. It came from another world and it still can imitate humans so well that real humans don’t know any difference. I wrote in my Alien posts how parasites are specialised. The thing is even more extra ordinary than aliens. The thing can be like other species not just use them as hosts. Compared to the thing aliens became believable. Just think about how complicated it has to be to get all memories, behavior and language from species from another world.