Who is The THING?

John Carpenter's 1982 Science-Fiction Horror masterpiece The Things follows a crew of scientists and engineers among others stationed in remote Antarctica. Once R.J. Macready (Kurt Russell) does some investigation, it is discovered that Norwegian scientists have come across an extraterrestrial ship lodged in the ice beneath them and have thawed out its only surviving passenger, all hell begins to break loose. Based on John W. Cambell's 1938 novella "Who Goes There", Macready and crew face off (see what I did there?) with a shape-shifting creature intent on surviving-- or even worse, escaping. In the last act of the movie the creature from another world is no longer being hunted but instead, it is studying and eliminating its obstacles that stand in the way of escape by trial and error. After the reality and severity of the situation settle in with the supporting cast, they begin to question and eventually turn on each other in fear of being dissected and consumed. The last twenty minutes of the film five members are presumably still alive when Macready makes the decision to split up, leaving Childs to guard the stronghold and taking Naul & Garry with him to check on the imprisoned Dr. Blair. That's when it happens -- Nauls sees Childs leave his post and then the power is cut, leaving the remaining men in the cold dark antarctic to battle The Thing

Childs or MacReady?

The ending scene we are treated to a delirious Macready, barely escaping the creature, struggling to stay on his feet among the blazes of what was previously his home. To the viewer's surprise, R.J. is not alone as Childs sneaks back into the frame and gives us one of the most prolific endings to a movie.

[Last 3 minutes of the fim]

Childs: You the only one who made it?

MacReady: Not the only one.

Childs: Did you kill it?

MacReady: Where were you, Childs?

(At this moment I believe it's an obvious giveaway that R.J. is still human, at no point in the film has the creature shown interest in pseudo hunting for its kin to blend in with the crew, able to split itself into multiple living parts if they were both the thing I believe this scene and its subtle nuances wouldn't have been added)

Childs: Thought i saw blair.. went out after him, got lost in the storm.

*Childs looks around at the burning base*

Childs: Fire's got the temperature up all over the camp... won't last long though.

MacReady: Neither will we.

Childs: How will we make it?

MacReady: Maybe we shouldn't...

(This is the dead giveaway, Childs is without a doubt the creature from another world. Less than fifty words has caused so much debate for three decades but it's fairly obvious after that. The nature of the thing was to imitate, the ability to become anything from anywhere. That honestly sounds like a fight or flight response and the events at the un-named scientific base were the byproduct of the Norwegians awakening this ancient being. Another dead give away is the attitude shift from the last time we see Childs alive and the perfect imitation of him at the end. Once shit hit the fan, as the majority of the film, Childs was self-reliant and headstrong about what to do in the situations only taking a backseat to R.J.'s seniority. Now interested in if MacReady suspects him and how he can survive the impending doom mother nature offers)

*Childs stares at MacReady with confused betrayal on his face*

Childs: If you're worried about me--

Macready: If we got any surprises for each other, I don't think we're in much shape to do anything about it.

Childs: ...Well, what do we do?

MacReady: Why don't we just wait here for a little while? See what happens..

*MacReady leans over slightly, passing Childs the bottle of "liqor" and slumps back over and visibly laughs after Childs drinks continuing to just watch the thing*

[fin.]

Continuing to put his life last, MacReady proposes the idea that it'd be best that both men die there instead of making it to safety in case the thing has survived. Taking context from what John Carpenter displayed in the film and the actions of the thing in this story, it would never self-sabotage in hopes to fool the human. Aside from the argument made, many believe that R.J. MacReady replaced the whiskey in that bottle with gasoline and once Childs drinks the liquid as if it really is Whiskey confirms R.J.'s hypothesis as he laughs in what I would assume is a victory.