ET's Mark Steines is talking to A-list actors Gerard Butler and Jamie Foxx, who star in the new action thriller 'Law Abiding Citizen.'

In the film, Gerard's character is out for revenge after his family is brutally killed and Jamie, who plays the lawyer who he believes betrays him, is his No. 1 target.

Gerard, who also produced the film, tells ET that he originally planned to play Jamie's character: "We originally offered Jamie my character, and I was playing the prosecutor. I'd always been playing the prosecutor but I figured that we heard through the grapevine he was interested in the prosecutor and I thought, well I would like to try my hand at the other role. ... We have a great chemistry together, and those scenes between us are gonna be electric."

Jamie says he found Gerard to be a little bit shy, but that he told Gerard, "Don't be afraid to let that go because when you do that, you're gonna be the bad guy that everybody roots for."

ET also spoke to the stars at the red carpet premiere last week in Los Angeles. 'Law Abiding Citizen' hits theaters October 16.