In the new thriller, The Accountant, by Gavin O’Connor (Miracle, Warrior), Christian Wolff (Ben Affleck) is a mathematics savant with more affinity for numbers than people. Using a small-town CPA office as a cover, he makes his living as a forensic accountant for dangerous criminal organizations. With a Treasury agent (J.K. Simmons) hot on his heels, Christian takes on a state-of-the-art robotics company as a legitimate client. As Wolff gets closer to the truth about a discrepancy that involves millions of dollars, the body count starts to rise. The film costars, Anna Kendrick, Jon Bernthal, Jean Smart, Cynthia Addai-Robinson, Jeffrey Tambor and John Lithgow.

Before he directed the film, O’Connor performed exhaustive research into the autism spectrum to ensure that Christian was as realistic as possible. In a possibly lesser known fact, he also performed exhaustive research into which fighting style would be most appropriate for the film. The movie features a fighting style that most audiences aren’t familiar with.

“It started with figuring out what his style of fighting would be. Doing a dissection of the character, it felt like Chris would just want to eliminate people as efficiently as possible in a mathematic way. There was a style of fighting we found called pentak silat. It’s an Indonesian style of fighting. Once we climbed inside the philosophy of pentak silat, it was very cinematic and kind of flashy, but it was very efficient.”

Fight scenes are very technical so they aren’t easy to direct. Surprisingly, the fight scenes weren’t the most difficult.

“The scene where we journey into Chris’ mind when he’s deconstructing the books, I was terrified of that scene. I probably overthought it, but I wanted to make sure we got it right. I kind of approached it like an action scene. It was a visualization of his superbrain.”

The Accountant shows flashbacks of Chris’ complicated relationship with his father. This was high wire act for the director as he wanted to show that the father’s borderline abusive actions actually sprang from love.

“When Ben and I started talking, the thing we agreed upon, was in the flashbacks, we wanted to make sure the audience understood him. When we meet Chris as an adult, we know how he came to be this person who had all these incredible skills. The flashbacks were always there. The thing that Ben and I did was change the flashbacks to dramatize his father. This was a dad who loved his child, but he was applying his own philosophical beliefs in a way to protect his kid because he knew it could be a cruel world out there for his kid. He wanted to make sure his child was prepared for that. His actions were always generated by love, but parenting isn’t a sport for perfectionists. He just did the best that it could. I hope it comes across that he really loved his son. Especially back then, we didn’t know a lot about the autism spectrum. The thing we kept learning about autism is that there’s no one thing for everybody. It’s different for everyone. We were just trying to depict it as honestly as possible.”

It’s not often someone on the autism spectrum is portrayed on the big screen. It’s even less often that someone on the autism spectrum is the lead character in a film. O’Connor discussed the research involved in portraying such a groundbreaking character.

“Ben and I always approached it from a place of honor and respect. I keep saying it’s a great time to be different. Let’s make a film about someone who’s different and celebrate it. He’s not different in a bad way, he’s just different. We’re all different. I love Chris and I wanted to honor him. If some parent has a child on the spectrum and goes, ‘that’s not my son.’ Well, we were just portraying Chris.

One day, Ben and I had a class with people on the spectrum and asked them questions to get as much knowledge as we could. Most of them were in Batman t-shirts [laughs]. Chris sort of became an amalgam of all these different details. We talked to so many people on the spectrum who are extremely witty. We watched the documentary, Asperger’s Are Us. It’s about four guys who have Asperger’s who formed a comedy troupe and do stand-up. It’s fascinating. We also met a guy who was a state championship wrestler. We were surprised over and over again.”

The Accountant opens in theaters October 14th.