Actor Chris Evans, along with other movie fans, was shocked to discover that the black and white film in Home Alone, Angels With Filthy Souls, is not a real movie. Home Alone, the classic Christmas film about an 8-year-old boy named Kevin McCallister whose parents accidentally leave him alone in their house during Christmas, features a scene where Kevin watches an old black and white gangster movie.

The old movie, titled Angels with Filthy Souls, is one that Kevin's parents wouldn't let him watch, but he indulges in it after he realizes that he has the house to himself. But after a pair of robbers target the house, Kevin uses some of what he learned in that movie to deter the would-be thieves in their efforts to break into the house. Even the movie's most famous line, "Keep the change, ya filthy animal," comes from Kevin's viewing of that film. Although the old movie seems violent, it also looks classic, like something that was very real back during Hollywood's Golden Age. It's even part of the reason many list Home Alone among one of the best Christmas movies of all time.

Related: Every Movie Franchise Disney Has Bought From Fox

Here's the issue, though: Angels with Filthy Souls is a fake old movie. It was filmed specifically for Home Alone, so only short clips of the "movie" even exist. What's more interesting, though, is that most Home Alone fans had no idea that this movie-within-a movie-was fake. One of those fans was Chris Evans, who responded to a tweet that Seth Rogen made about it. See Rogen's and Evans' tweets below.

So many people were shocked by the news that Angels With Filthy Souls is fake, Twitter gathered a bunch of tweets about it into a Twitter Moment called "When you find out the movie Kevin watches in Home Alone isn't a real one." Further, Evans wasn't the only one in Hollywood shocked by Rogen's revelation. Spider-Man: Into the Spider-Verse co-director Rodney Rothman also responded to Rogen's tweet with surprise, as well as comedian/actor Nick Kroll. See Rothman and Kroll's tweets below.

Although this fact may shock many fans of Home Alone, the film remains as iconic as ever. Macaulay Culkin even recently reprised his role as an adult Kevin in a Google Home commercial that had his character using Google Assistant to set some of the traps he used in the original movie. There are also plenty of Home Alone jokes and parodies, and some fans have created a different version of the film with additional blood and gore. The franchise even spawned five sequels, although only the second movie, Home Alone: Lost in New York, featured the original cast.

Home Alone continues to capture the hearts and imaginations of Christmas movie fans, including Ryan Reynolds, who wants to re-imagine the movie as an R-rated story. But even among its most die-hard fans, many are just now learning that Angels with Filthy Souls isn't real and are shocked by that fact.

More: Home Alone Recut As A Horror Movie

Source: Seth Rogen, Chris Evans, Twitter, Rodney Rothman, Nick Kroll