Even Macaulay Culkin didn't know the gangster movie in 'Home Alone' is fake

It's the end of the year, but it isn't too late to learn something new before 2019!

Seth Rogen — and a number of Twitter users — didn't know that the old movie Kevin McCallister watches in Home Alone isn't a real movie. In a tweet, Rogen said he believed Angels With Filthy Souls was an actual movie his "entire childhood."

And Macaulay Culkin, who plays Kevin in the film, did too!

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In fact, the movie-within-a-movie is a parody of old gangster films like the 1938 film Angels With Dirty Faces. The fake film is the source of one of the most iconic holiday phrases in pop culture: "Keep the change, ya filthy animal."

Twitter users were pretty surprised to learn that it isn't a full movie — including Chris Evans.

Well this tweet just taught me it isn’t. — Ｂｅｃｃａ Ｆｒａｓｉｅｒ (@bexmix) December 26, 2018

It isn’t? (Dead serious) — nick kroll (@nickkroll) December 25, 2018

I was today years old when i founded out it was fake. Thanks Seth Rogen. — Laterice Rule (@Queensocialphob) December 26, 2018

@Sethrogen .... I rescind you Canadian Citizenship for 23 hours for ruining my Christmas. — Jason Dussault 🇨🇦 (@JasonRDussault) December 26, 2018

Another Twitter user suggested making a full length version with Culkin as the lead.

I really hope Macaulay Culkin stars in a real production of Angels With Filthy Souls so Home Alone can be ultra meta — Aubrey Perin (@MaybeAuthentic) December 26, 2018

Nick Kroll, Seth Rogen, and Chris Evans can all make cameos in it too!