In the action film "Den of Thieves," where the line between the good guys and bad guys is fuzzy at best, Gerard Butler plays a hard-drinking cop who, the says, is such a warrior in the streets that "he's a danger to a lot of people, including himself."

"I'm a bit intimidated by myself in this," he tells Made in Hollywood reporter Kylie Erica Mar. "I have to say, I'm watching and I'm going: Oh, my God, that's a badass."

https://www.youtube.com/watch?v=F5nIHxeQFwE

 

Butler's Nick O'Brien leads the Regulators, an elite unit of the Los Angeles County Sheriff's Department that goes up against Ray Merrimen, played by 50 Cent, the recently paroled leader of the Outlaws, a gang of highly trained ex-military men seeking to pull off a heist of the city's Federal Reserve Bank.

To prepare for the on-screen clash, the two groups of cops and robbers staged separate boot camps and only got together when they were on set.

"We had bigger weapons," says 50 Cent. "They had the tactical law enforcement training while we had military stuff. So we had the big machine guns and stuff like that."

"It's true," adds Butler. "They did a lot weapons training. They're ex-military and a big thing for them was to show their cohesiveness and how well they work together and their discipline, and that's what's so dangerous about them. For ours, we spend a lot of time with cops talking about mentality, talking about procedure, and then we would go out in the gun range."

Butler's group also went white-water rafting and paint-balling and visited an escape room.

"That was amazing how that helped form our bond," he says. "I formed a bond with those guys like I never formed on a movie and we're still all great friends. You see their bond on film. You see our bond on film. And it really worked. We stayed separate for most of the movie."