Mark Ruffalo found a delicious way to prepare for his latest role, and it involved plenty of Philly cheesesteaks. 

The 57-year-old actor is stepping into the shoes of an FBI agent in HBO’s upcoming crime drama Task, which follows a task force determined to put an end to a string of violent robberies in Philadelphia.

While attending the All the President’s Men benefit reading for the Center at West Park on Aug. 25, Ruffalo revealed how he immersed himself in the city’s culture during filming. 

“I ate a lot of Philly cheesesteak sandwiches,” he told PEOPLE, admitting the preparation wasn’t exactly strict training. “I just put a bunch of weight on.”

The Avengers star also did his homework to make sure his on-screen performance felt authentic. 

“I spent a lot of time with FBI agent Scott Duffey. That’s about the most I did,” Ruffalo shared.

For now, his attention is on promoting the new series. “My main focus is doing a bunch of press. I’m really excited about it,” he added.

The show, premiering Sept. 7, also stars Ozark alum Tom Pelphrey as Robbie, a father of two who becomes entangled in crime. 

According to the official synopsis, the series is “set in the working-class suburbs of Philadelphia” where Ruffalo’s character leads a task force determined to stop a dangerous string of robberies led by an unsuspecting family man.

With a mix of gritty storytelling and Ruffalo’s signature dedication, Task is already shaping up to be one of HBO’s most talked-about new dramas.