Jerry Welbach (Brad Pitt) is a low-level Mafia "mechanic" whose ineptitude is countered by frequent (but unpredictable) bursts of dumb luck. Jerry's girlfriend Samantha (Julia Roberts) wants him to get out of the business, and after his latest blunder lands capo Arnold Margolese (Gene Hackman) in jail, so does mid-level crime kingpin Bernie Nayman (Bob Balaban). But Bernie insists that Jerry do one last errand for the mob before they let him find employment elsewhere — he has to go to Mexico and recover a rare and very valuable pistol, which is said to be cursed. While Samantha objects to Jerry taking the assignment, he isn't in much of a position to argue; Jerry heads south of the border, while Samantha, in a huff, sets out for Las Vegas. Once in Mexico, Jerry finds the pistol easily enough, but making his way back to the States proves to be an unexpected challenge. Meanwhile, Jerry's superiors want insurance that he'll return with the goods, so they hire Leroy (James Gandolfini), a hitman, to kidnap Samantha and hold her hostage until Jerry comes back.