Director Brian Helgeland's cut was significantly changed by producer/star Mel Gibson before release and was 15 minutes shorter than the final version. Here are some of the differences to Gibson's highly publicized reshoot version of the film that was released into the theaters.
* The opening shot of Porter in the doctor's office is not in Helgeland's cut. The film begins with Porter on the bridge returning to the city. Brian's cut doesn't suggest the double-cross until we see the flashback.
* A more harsh exchange when Porter visits Rosie (Maria Bello) for the first time.
* Odds and ends with Val Resnick (Gregg Henry) throughout the film. Includes a curbside threat to the David Paymer character and a funny scene calling Pearl (Lucy Liu) on the phone.
* In Helgeland's version, Porter does not merely appear in Resnick's hotel room in the mob hotel. He sets fire to a garbage truck to distract the hoods out of the hotel lobby, then has a nasty encounter with another hood in the hotel elevator, eventually leaving the hood unconscious with the elevator doors banging open and closed on his head. Gibson describes this scene in an interview in Premiere Magazine: "I get on an elevator with some guy," Gibson says with relish, "the guy notices I'm not supposed to be on the elevator and the next time the doors open you see that I've ripped the guy's eye out. Then I see him later as he's going into some office, and I say, 'Oh, it's you again, Cyclops' and I poke the guy's other eye out."
* A small exchange between Porter and the Asian gang.
* When Val breaks in and beats up Rosie, Porter the dog gets shots in the head and remains dead. In Mel's cut, the dog lives.
* The two versions of the film begin to change greatly when Porter confronts Fairfax (James Coburn). The dialog is different and the outcome of the scene is changed.
* The Kris Kristofferson character of Mel's cut replaced a female "Outfit" boss voiced by Angie Dickinson. She's never seen in the film. When Porter begins to kill her associates, the boss almost immediately gives in to Porter's demands. In Mel's cut, the boss was a bigger character and provided a bigger climax. All the boss's son and torture scenes are not in Brian's cut of the movie.
* The climax of the film takes place on a mass transit platform. Porter arranges to pick up his cut of the money, but the boss dispatches hitmen to stop him. He gets the money, but is shot in the chest. Stumbling out of the station, he drops the bag and a homeless man picks it up. Porter refuses to put up a fight and begins to die. Rosie finds him and slaps him back to life. Porter suggests a doctor he knows can patch him up. The final shot is of the two driving out of town.