Ethan Hawke has spent the better part of his career avoiding genre projects: although his first film was Explorers and he helped launch writer-director Andrew Niccol’s career when he starred in Gattaca, he’s otherwise done a lot of great work in comedies, dramas and independent films.

But the actor says he decided to appear in Scott Derrickson’s Sinister because of a longstanding relationship with its producer, Jason Blum, whose work in the Paranormal Activity franchise made him the perfect collaborator.

“If I really ever wanted to make a horror movie, this is the moment to do it,” Hawke tells Celebuzz. “[Jason] and I were partners in running a theatre company when we were about 20 years old… It was the right script with a great director with a producer I respect. It started to feel right.”

What challenges did Hawke face trying to make his true-crime novelist character charming?

In the film, Hawke plays a successful if self-important writer of books about real-life crimes. He says that a character like that is more interesting specifically because he might not do “the right thing.”

“You always know what a good person is going to do,” he observes. “They’re going to do the right thing. And if they have some moral complexity, you’re never sure what they’re going to do because their motivations are askew. And as an actor that makes it more fun to get inside a character like that.”

Sinister opens in theaters nationwide on Oct. 12. Watch the film’s trailer below.