Steve Jobs isn’t following the typical biopic formula — director Danny Boyle and screenwriter Aaron Sorkin constructed the film in three acts to mirror the launch of three iconic Apple products. As such, it will hopefully offer riveting glimpses into the life of the Apple co-founder and CEO. But the format of the film isn’t the only unconventional aspect of production. According to co-star Michael Stuhlbarg, Boyle and Sorkin had a very interesting and somewhat unusual approach to shooting the film.

Stuhlbarg plays Apple Macintosh employee Andy Hertzfeldt opposite Michael Fassbender’s Jobs in the film, which is presented in three acts — similar to a theatrical production. During a chat with Collider, the actor revealed that the shooting process somewhat mirrored the film’s interesting structure:

[T]he Steve Jobs rehearsal process was unlike anything I’ve ever done to this point and probably unlike anything I’ll ever do again. Aaron Sorkin wrote it very much like a three-act play, and each act was a launch of a new product. So we rehearsed each act for two weeks and then we shot for two weeks; then we rehearsed for two weeks and shot for two weeks; then we rehearsed for two weeks and then we shot for two weeks.

And that was amazing because by the time we were ready to shoot, we were really, really ready, and it brought us all together in an extraordinary way. Also, it kind of gave us something in the telling of the story that you don’t often get, which is a sense of momentum, of what a story is telling you. He got the opportunity to get the barrage of nonsense that was being thrown at him throughout the entire story. It was just unlike anything I’ve ever done before.

Screenwriter Aaron Sorkin is known for being incredibly precise with an intense attention to detail and dialogue specifics. Stuhlbarg also spoke a bit about Sorkin’s heavy involvement in the filming process:

He was sitting with us in the room while we were rehearsing, so he would say “That little flub or something you just happened to do? Let’s add that in,” or “Say that word and then a comma and then a dot, dot, dot, and say it again afterwards.” So he was constantly refining and retooling. The specificity was insane and I loved that because they hear it a different way, or they hear it the way they want us to do it. I want to completely please the playwright/screenwriter.

Most films have a shooting schedule that isn’t chronological, nor do directors typically insert rehearsal periods in their schedules. But given the play-like structure of the film, it makes sense for Sorkin and Boyle to treat the production itself like a play, allowing for actors to rehearse and workshop their performances while the director and screenwriter continue to tailor the project.

Hopefully their dedication to the project yielded great results — the trailer certainly seems to indicate something special. Steve Jobs also stars Seth Rogen, Kate Winslet and Katherine Waterston, and hits theaters on October 9.