AceShowbiz - Filmmaker Scott Derrickson walked away from the "Doctor Strange" sequel because he couldn't imagine another director taking charge of his new horror passion project, "The Black Phone".

Derrickson scored a big hit for Disney/Marvel with the original 2016 blockbuster, starring Benedict Cumberbatch as the titular superhero, and was due to return for the planned follow-up.

However, he ended up stepping down from "Doctor Strange in the Multiverse of Madness" last year (2020) as a result of "creative differences", and screenwriter C. Robert Cargill, who penned the first film and also departed the sequel, admits the decision was partly down to Derrickson's wish to focus on their latest collaboration, "The Black Phone".

Cargill told CinemaBlend.com, "It was creative differences. [Derrickson] wanted to do one movie, and Marvel wanted to do another movie. So he sat there and said, 'Well s**t, I've got this great script that I wrote with Cargill, and I'm really proud of it.' "

He continued, "We were actually going to go out to other directors for 'The Black Phone', and Scott... called me up and said, 'Dude, I have to make this movie. It's gotta be my movie, I have to do this.' "

Cargill also explained how Derrickson - who was replaced behind the camera for the Marvel Cinematic Universe (MCU) film by Sam Raimi - was keen to direct a project he had total control over.

The screenwriter recalled, "It came down to Scott, and Scott's like, 'Well, I can make this movie that I'm compromising what I wanted to do on, or I could make The Black Phone', and he goes, 'You know, I want to make a movie with Cargill. I'm gonna go make The Black Phone.' "

"It was, as he said publicly, it was a hard choice to leave Strange behind; but it made it easier that he had a movie that he was looking forward to. And then the experience was so great that we're just are so proud and happy with what we made."

"The Black Phone", based on a short story by Joe Hill, stars Ethan Hawke and is expected to be released next year (2022).