For Jamie Foxx, the Oscar-winning star of Taylor Hackford's 2004 biopic Ray, the decision to play one of the leads in the new thriller Law Abiding Citizen was easy.

“I know when I want to work with certain people,” says Foxx, 41. “I remember the feeling that I had when I saw 300. Gerard Butler was at the top of his game in that movie, and I immediately wanted to do a film with him. On top of that, [Kurt Wimmer's script] tells a cool, interesting story.”

In Citizen, Foxx plays Nick Rice, a cocky Philadelphia prosecutor assigned to handle a brutal home invasion. When Nick offers one of the suspects a light sentence in exchange for testifying against his accomplice, the surviving victim of their brutality – Clyde Shelton (Butler), a devoted family man whose wife and daughter were slaughtered in the attack – takes exception.

“A crazy chain of events turned his life upside down," Foxx explains. "[Clyde] thinks, ‘How could this happen to me? I’m a good guy, I haven’t hurt anybody. I get up, I go to work, I go to church. I pay my taxes, so how could this happen to me?’”

Rather than continuing to play the good, grieving victim, Clyde eventually goes on a rampage: A decade later, the man who got away with murder is found dead, and Clyde casually admits to the crime. He then issues a warning to Nick: Either fix the justice system that failed his family, or other key players in the trial will die.

So begins the latest offering from Italian Job director F. Gary Gray, which puts Foxx and Butler's characters on an explosive, corpse-laden collision course.

“What I have always loved about this movie is how closely Nick and Clyde are bonded together,” says Butler, 39. “They are like two warriors coming head-to-head. Despite the fact that they’re out to destroy each other, there’s a certain respect. One of the points Clyde is making to Nick is that this could just as easily be him in the same situation.”

“Gary came on board and gave life to the words on the page. We had a great script, but the film is so much better. It’s exciting to look at. The drama comes across brilliantly and he got great performances from all the actors.”

For free passes to see Law Abiding Citizen tonight at the San Francisco Metreon at 7:30 p.m., simply send your name, address and phone number here. Winners will be contacted early this afternoon.