John Carpenter’s The Thing is a grotesque, timeless horror film that’s been beloved by fans ever since its premiere in 1982. We’ve watched it and re-watched it over and over again, cozied up in our homes with the lights off (well, maybe one left on, just in case), but according to cinematographer Dean Cundey, it appears there’s one hugely important detail that a lot of people have missed.

Why are we all learning this now? According to the folks at /Film, The Thing has a 4K Blu-ray release coming out from Scream Factory in October, which contains a commentary track from Cundey moderated by Blumhouse blogger Rob Galuzzo.

The Thing’s titular monster is a perfect villain because it can imitate any being — human or animal  perfectly. You have essentially no idea where it could be hiding, or whose form it could be hiding in, until it grows spider legs from its head and goes skittering out the door. (Just to be safe, there are SPOILERS for The Thing coming up.) At the end of the film, only two people are left who survived the alien’s rampage: R.J. Macready (Kurt Russell) and Childs (Keith David). They both appear to still be human, although we can’t be totally sure.

On the commentary, Galuzzo asked Cundey whether he and Carpenter had come up with any subtle cues about the alien for the audience to pick up on. Cundey said that there is a way, if you pay very close attention, to figure out who is human and who is not. “You’ll notice there’s always an eye light, we call it, a little gleam in the eye of the actor,” he says. ”It gives life.”

Check out this clip from the end of The Thing, and see if you can tell for yourself whether these two are human or not:

The 4K Blu-ray of The Thing comes out October 11.

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