There is a heavy B movie feel to this but it is a damn good B movie. It packs quite a few genuine scares and definitely enough suspense to hold your attention. I am also quite impressed by the visual effects used smartly and only when required. Acting could have been a lot better though.
Set in Antarctica, the movie starts with a Norwegian member of a different station chasing a dog on his helicopter and in the act ventures into the American station's territory and injures one of the members while fully absorbed in his mission. They put him down, take the dog and decides to investigate what is going on in their camp. When they realize that a shape shifting Alien is among them consuming and imitating one crew member at a time, they stop trusting each other and more so themselves.
The starting sequence is eerie that pans out quite leisurely with simple yet terrific background score. The build-up to the Thing could have been a little more progressive like in 'Alien' than one guy listing down what all it is capable of just by examining it's blood sample. Where the drama triumphs is the tension between the characters to trust each other than the fear of the Thing itself. It does have innumerable logical loop holes but clever enough screenplay that puts them on the background. There isn't enough emotion captured be that of fear or disappointment of not be able to make it back home.
Some terrific scenes to look out for -
1. The dogs scared to death when the Thing put in their cage transforms for the very first time.
2. The starting sequence.
3. Some fantastic visual effects for the time - a man's head parting from the body developing spider-like legs and crawling off.
4. When the Thing transforms while all the crew members are tied to a bench.
It may not live up to your expectation if you believe in all the hype around it. But with smart visual effects and leveraging on the drama potential the plot had - it is a decent horror movie.