I’ve watched this film countless times; I actually own it on DVD twice, plus versions in 4K, Blu-Ray, and even HD-DVD, which is no longer around. Looking back, I really regret not seeing it when it was first released in theaters in 1982. I can't quite recall why I didn’t go—I certainly would have been old enough to appreciate it. Instead, I ended up seeing "E.T." and got caught up in the excitement surrounding that movie. I just went along with what everyone else was doing. All I had to do was move to a different screen to experience Carpenter's film and its unsettling atmosphere. It’s too bad I missed it. Like all truly great movies, music, or books, each time I watch it, something new strikes me. I constantly try to figure out how the Thing managed to spread throughout the camp. I look for hints and clues. For example, there's a moment when Blair is performing an autopsy on the creature that’s been burned, and while he’s explaining his theories about what the Thing is, he absentmindedly taps his pencil eraser against it, crosses his arms, and brings the eraser dangerously close to his mouth. Then he makes a point by waving the pencil around, and for just a second, it touches his lip! Did that mean he infected himself? Is there anything he can do about it now? Has the Thing spread to Blair?!?! Moments like that are woven throughout the film. It’s incredibly suspenseful and paranoid, and the feeling of isolation is agonizing. You know these men have nowhere to escape to; all those unnamed individuals—well, they aren't truly nameless, but it’s hard to keep track of them all. And strangely enough, we still seem to care about their fates. I think Carpenter has done such a fantastic job building tension through threat and isolation that we naturally find ourselves imagining what it would be like to be in their situation. There are so many memorable scenes. The opening sequence with the helicopter chasing the dog is gripping. Then there’s the horror of discovering the Thing in the dog pen, and Norris's death and subsequent transformation—it's shocking! It's quite gory, too, and I think that level of gore is essential to the story. That’s one criticism some people have leveled at this film: it’s considered excessively graphic. And it is, but given that it's about a creature so alien and without any recognizable form, it all seems appropriate. And those effects—I don’t think I need to add anything more than what others have already said about the amazing practical effects by Rob Bottin; they are simply the best I’ve ever seen. Then there's the "blood test" scene. All of the men at the Antarctic research station voluntarily submit blood samples and then watch them being tested while they’re tied to chairs, in an attempt to determine which ones are actually the Thing. One by one, a heated wire is placed into a petri dish containing each man’s blood. Seeing the smoke rise from the wire when it touches the dish provides some temporary relief. Will the next sample be clear? You'll have to watch it yourself to find out. The way this scene is set up and carried out is among the most intense and frightening things I’ve ever witnessed. I am glad that home video helped this film gain recognition; now it’s considered a Horror/Sci-Fi classic. It’s without a doubt my favorite horror movie, possibly my favorite monster film, and quite possibly my top science fiction feature. It's really that good.

Source on TMDB