The film was originally going to be directed by Carey Fukunaga, who wanted to see Will Poulter play the role of the macabre Pennywise. But sometime after he left the project in 2015 due to creative differences, Poulter also withdrew from the film. It is assumed that he did it out of solidarity, or he was kicked out.

However, Andrés Muschietti, the new director, refuted these assumptions in an interview. He stated that he was also interested in collaborating with Poulter, but the actor expressed doubts about being a good fit for such a dark role.