Aaron Paul on what it’s like to go on a ride along with cops

Acting always entails research, but “Triple 9” is a different story. In the new thriller, Aaron Paul plays a disgraced ex-cop who’s part of a gang of thieves filled out by former mercenaries and corrupt police officers. That meant doing ride alongs with the LAPD through East L.A. What he saw could have come right out of a movie, and not just “Triple 9” itself.

“We pulled over this guy — I forget his name, but it was something that’s terrifying, like ‘Psycho,’” the actor, now 36, recalls. The cop arrested him, finding a gun whose serial number had been shaved off. He had had two strikes against him, meaning he’d be in jail for the rest of his life. When they got back to the station, Paul wound up interviewing him, despite finding him to be the scariest person he’d ever seen. Then he got a surprise: “Turns out he was a big fan of ‘Breaking Bad.’”

Every cast member from “Triple 9” has stories like this; Paul recalls one from co-star Casey Affleck’s own ride along, which involved a stand-off that ended with a perp leaping out of a window holding an infant in one hand, an AK-47 in the other. For Paul such tales stressed how real the film is — how the worst things we see in “Triple 9” and “Breaking Bad” oftentimes really happen.

Paul came away with a lot of respect for cops — he emphatically recommends doing your own ride along — but also an understanding that there’s no clean line between good and bad.

“You would see these little kids, 7 or 8 years old, on their bikes. They’d see us pulling up, and they’d jump off their bikes and run into a store,” he recalls. Paul would watch the cops run after them and come back with proof they were selling drugs for a gang. “These kids don’t have a choice. It’s all they know. For the adults it’s all they know. They’ve grown up on the streets their whole lives.”

For Paul, “Triple 9” isn’t just another gig about the underworld; it’s a film where he gets to again play an addict. And Paul didn’t want to be typecast forever in the “Breaking Bad” world.

“I definitely got a lot scripts sent my way for drugged-out characters. That’s the last thing I wanted to do,” Paul says.“Triple 9” was an exception, and not only because of its comically large name cast (in addition to Affleck, there’s Chiwetel Ejiofor, Anthony Mackie, Norman Reedus, Woody Harrelson and Kate Winslet, playing a Russian mafioso). The director, John Hillcoat, has a reputation for dark, brutal films about violence, including “The Proposition” and “Lawless.” Paul knew it would be an honest but humane look at the moral gray zone. No character, from cops to robbers, is all bad or all good.

“You’re not sure who you’re supposed to be rooting for. You’re kind of rooting for everybody, and you don’t know why,” Paul says.

It also meant doing action, which is something he’s not done often, excepting sitting in a car and cruising across the country in “Need for Speed.” Paul has spent most of his acting career doing more talking than fighting, but for someone used to tearing into deep and often shouty emotions, painstakingly filming “Triple 9”’s kinetic opening heist set piece wasn’t boring too shoot.

“As a kid I played cops and robbers. We all did. This was just playing it on the biggest scale possible,” he says. “We got to put on a mask, run around with rubber guns and rob a bank and not get into trouble for it. We’d joke around and have a laugh while they set up the next shot.”

Even playing an addict again had more than a whiff of nostalgia: “It brought back a lot of fond memories of smoking meth onscreen,” he jokes.

Follow Matt Prigge on Twitter @mattprigge