IT or IT: Chapter One took the world by storm in 2017. Raking in over $US 700 million at the global box office — the highest ever for a horror film — and garnering positive reviews from critics as well. The Stephen King adaptation is scary, weird and filled with genuinely interesting teen characters. Director Andy Muschietti didn’t resort to cheap and meaningless jump scares and instead told a character-driven coming of age story with authentic tension and atmosphere. This September will see the release of IT: Chapter Two, in which the kids from the first movie have grown up into Jessica Chastain, James McAvoy, Bill Hader, etc.

In the first movie, Andy Muschietti and his sister/producer Barbara Muschietti worked together with screenwriter Gary Dauberman based on the skeleton and structure laid out by previously attached filmmaker Cary Fukunaga (Beasts of No Nation) and his co-writer Chase Palmer. This time, though, the Muschiettis and Gary Dauberman got to adapt the second part of the Stephen King novel entirely by themselves.

In an interview with Collider.com, Andy and Barbara Muschietti compared and contrasted the writing process of the first film and the second film. When asked how early they started working with Gary Dauberman on the screenplay, the duo said:

BARBARA MUSCHIETTI: August. I think it was before we came out with Chapter One. We were already working on ideas and then Gary [Dauberman] started putting it together with Andy. You know Andy’s very much the mastermind of the story and he knows very well what movie he wants to make. So we had a great journey with Gary. And then when Gary left for Annabelle, we started working with Jason Fuchs who did an amazing job taking us to the finish line. It was great. Yeah. I’m very happy.

ANDY MUSCHIETTI: Yeah. And having Jason on also during the shoot.

BARBARA MUSCHIETTI: Yes.

ANDY MUSCHIETTI: It was a weird thing because there were things changing every time. The great thing about staying open in on set [is] new things appear and new questions are asked, so it’s not an iron script anymore. So okay, “We still didn’t shoot Scene 74, so we are going to translate this question into that.” That was what was great about having a writer during production. So, Jason did a great job.

BARBARA MUSCHIETTI: You know that stereotype of getting new pages every day? We were getting new pages every day [laughs]. But it’s good, you make it better. It’s about making the movie better.

This does make me slightly concerned about the film. Sure, making script edits on set after production has already commenced is nothing too out of the ordinary. But it’s not a good sign either. Then we also have writer Gary Dauberman, the man who penned Annabelle Comes Home and The Nun, both absolutely lousy horror films. A part of me wonders if maybe that’s why Jason Fuchs was brought in — to iron out the kinks in Gary Dauberman’s screenplay. But then again, Fuchs isn’t exactly the best screenwriter in the world either considering his resume includes I Still See You and Pan. Having said that, the success of the first film should give us enough reason not to doubt director Andy Muschietti.