Looking back on the It mini-series from1990, it is easy to see that they got their design for Pennywise from the clowns of the time. However, in the reboot the character seems to take his design cues from clowns of the 19th century.
It reboot director, Andy Muschietti, sat down with Collider during their set visit to chat about the film, and the look of Pennywise was brought up. The director was asked about the phrase he had used to describe Pennywise as an "ancestral clown," and to speak a little more about his appearnce. "Yeah. Well, the fact that this entity has been around for thousands of years… I’m more drawn— I never— aesthetically, I don’t dig the 20th century clown," he explained. "I think it looks cheap, and it’s too related to social events and stuff and circus and stuff, which circus is fine, but I’m more aesthetically attracted to the old time, like the 19th century clown. And given that this guy has been around for centuries, I wondered myself why, why not, having an upgrade that was 1800s."
He was then asked to speak about his early designs for the character, and how they developed over the course of pre-production. "I had a sketch. One sketch. It was like a baby. It was like a Gerber baby," he said. "With something very off, because his eyes were wide-eyed – the eyes like, slightly apart. And then, to be honest, it didn’t evolve much from that point. And then the Pennywise you saw today is special because his hair is crazy, but the rest of the movie is different. I’m playing a little bit with his mood, and his mood sometimes in terms of the hair. There’s like two hairs maybe. But the official shape is more like a weird baby."
It will be released on September 8, 2017.