Carrying out mysterious and sometimes dangerous tasks in his tricked-out BMW, Frank adheres to a strict set of rules, which he never breaks. Rule One: Never change the deal. Rule Two: No names - Frank doesn't want to know whom he's working for, or what he's transporting. Rule Three: Never look in the package.

Frank's newest transport seems no different from the countless ones he's done in the past. He has been hired by an American known only as "Wall Street" (see Rule Two) to make a delivery, but when Frank stops along route, he notices his "package" is moving. Violating Rule Three, Frank looks inside the bag, finding its contents to be a beautiful, gagged woman Lai(Shu Qi).

Frank's steadfast adherence to his other two rules - which make up his basic code of survival - also quickly falls, hurtling him and his new companion on a road leading to shocking secrets, deadly complications, and the last thing Frank ever expected to come to believe: that rules are made to be broken.