IT post-credits scene with Jessica Chastain was cut from the first movie

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However, Muschietti revealed that plans were made to add a post-credits sequence to the first film, with a scene setting up Chapter Two, but it ultimately had to be scrapped.

“Something a lot of people probably don’t know is ‘Chapter One’ did have the idea to make a post-credit scene, which was Beverly Marsh picking up the phone,” Muschietti said. “So, 27 years later, post credit, you would see a phone ringing. It’s an iPhone, so it’s impossible that it’s 1989, and a hand comes in and the camera wraps around this red-haired back of a head, and we turn around, and it’s Jessica Chastain!”

Chastain plays the adult Beverly in IT Chapter Two, which is set 27 years after the first film, in which Sophia Lillis played the character.

Ultimately, it was Chastain's busy schedule that meant this scene would never be shot and incorporated into the original movie.

IT Chapter Two sees the Losers' Club reunited with the terrifying 'clown' Pennywise who haunted their childhoods and, as Muschietti suggests, the movie comes to a quite definitive conclusion – you can read our analysis of the film's ending right here.