A close encounter of the worst kind.
Full disclosure: When John Carpenter's remake of THE THING came out, I didn't like anything about it other than the now-legendary practical special effects. You see, I approached it with a prejudicial hatred based on how much I loved the Howard Hawks version from 1951, and to my still-in-high-school perceptions, the remake was both blasphemous and dull. Then, sometime a few years later, I saw Carpenter's remake again, and that time I finally got it. Admittedly, my young mind had been dulled by the steady avalanche of the 1980's slasher boom, so I was perhaps not in the proper head space for anything more challenging at the time, but whatever the case, Carpenter's THE THING has since gone on to become one of my favorite horror films for a number of very good reasons.
In a nutshell, the story revolves around the terrible fate of a group of researchers at an Antarctic base who stumble across a hostile extraterrestrial life form that can absorb other living creatures and flawlessly duplicate them, and if a piece is cut off of the alien, that individual piece will now function as a separate entity possessing the same shapeshifting capabilities, so the only way to put a stop to it is to immolate it until nothing remains but charred ashes. The creature of course manages to imitate and replace assorted members of the team, and the group swiftly falls victim to frayed nerves and understandable paranoia as no one among them can be trusted. And once the creature's nature and capabilities are understood, it's clear that it cannot be allowed to escape from the remote Antarctic base, lest is reach civilization and begin its imitation/assimilation tricks on a scale that will spell the end of mankind. The Thing is also highly intelligent, having crash-landed on Earth untold ages ago in a flying saucer, and now that it's once more awake and active, it seeks to repair its spaceship and leave...
Examining one of the Thing's twisted hybrid forms.
Poster from the American theatrical release.