Warning: This article contains major spoilers about Us. Read at your own risk!

Jordan Peele‘s hit horror film Us has several horror movie-referencing Easter eggs, from the setting of Santa Cruz, Calif. — where much of the 1987 vampire tale The Lost Boys was shot — to the presence of twins played by Noelle and Cali Sheldon, a nod to the creepy sisters in 1980’s The Shining.

But the most important, and potentially revealing, of the film’s Easter eggs is likely one which is not being picked up by the majority of cinemagoers.

Early in Us, we clearly see a videotape with “CHUD” written on its side. What is “CHUD”? Glad you asked! CHUD — or, more accurately, C.H.U.D. — stands for Cannibalistic Humanoid Underground Dweller and is the title of a low budget 1984 horror film. Starring Daniel Stern (Home Alone, City Slickers) and John Heard (also Home Alone), the movie concerns monstrous, and murderous, humans who live in subterranean tunnels. The movie’s plot, of course, also bears a passing similarity to Us, in which a family is threatened by doppelgängers who, writer-director Peele ultimately reveals, have been dwelling beneath the surface of the earth.

C.H.U.D. earned more than $4 million at the box office, inspired a sequel (1989’s C.H.U.D. II: Bud the C.H.U.D.), and has become something of a cult favorite over the years. In a 2014 interview with the A.V. Club, Stern even mentioned that he had hopes of turning it into a Broadway musical.

“That’s a movie that we put together, just friends,” Stern said. “Everybody in it was a friend. Our friend wrote it. He had the idea for C.H.U.D. John Heard, Christopher Curry, and I starred in it. The director was a friend… The people who turned to C.H.U.D.s were just actors who turned into cannibals. But then in order to sell it as a horror movie, they added in these terrible slimy things. It wasn’t quite what we’d wanted to make it, but the experience of making it really showed me how to make a movie.”

Watch the trailer for C.H.U.D. — if you dare! — above.

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