Here's what IMDB's blurb says:
"An ex-con sets out to avenge his brother's death after they were double-crossed during a heist years ago. During his campaign, however, he's tracked by a veteran cop and an egocentric hit man."
That pretty much tells you everything about the story you need–or want–to know. It's a straight-ahead vengence story, no frills, no surprises. (There's an alternate-ending, if you see the DVD, and I can see why they didn't use it. It's dramatically-inferior, and there is also a big gun-flub in the alternate version, where a pistol magically goes from battery to locked-back empty that would have had the gun guys howling in the seats ...)
Johnson ("The Rock") is getting better as an actor. Billy Bob Thornton doesn't need to get any better. The rest of the cast is adequate, and it's one of those where the main characters also don't need (and mostly don't have) names, ID'd only by generics: Driver, Killer, Cop, Warden, Preacher, Old Guy, Teen Girl ...
As I say, a guilty pleasure. Your mileage will probably vary ...