The ending to director John Carpenter's 1982 sci-fi/horror classic The Thing has been debated for years. In a movie featuring an alien that can mimic human behavior and appearance, can we really trust that MacReady (Kurt Russell) or Childs (Keith David) are really who they say they are when they're both sitting together at the end?

Over the years fans have dissected every frame of that last moment, even studying the way each character breathes. But now, more than 30 years after the movie premiered, cinematographer Dean Cundey has revealed that he and Carpenter included a subtle lighting trick to help audiences be able to tell which characters are human and which are, well, the thing. In the commentary track for the new 2K Blu-ray release of the movie from Scream Factory, Blumhouse writer Rob Galluzzo interviewed Cundey and revealed what the cinematographer had to say about these visual cues:

"Early on in the commentary track, I asked Cundey if he and John discussed doing a subtle lighting trick to imply who might be 'the thing.' He waited until the blood scene to answer my question. As the scene began, he explained, 'So we were looking for some kind of a subtle way, to say which one of these (men) might be human. You’ll notice there’s always an eye light, we call it, a little gleam in the eye of the actor. It gives life.'"

So what about that final scene? Well, you might want to wait until the new Blu-ray hits shelves in all its HD glory this October to get a clear answer, but for now you can brave the video below to try and figure out whether Russell or David has that little glint in their eye.

[h/t iO9]