Centering around Sheriff's Deputy Lou Ford (Casey Affleck), Killer starts out simple enough. Ford gets sent to run off a prostitute (played by Jessica Alba), operating out of a shack on the outskirts of town. They become entangled, and begin a side relationship, even though Ford has a girl, Amy (played by Kate Hudson), at home. When things get complicated between Joyce (Alba) and Chester Conway, the father of a young man obsessed with Joyce, Ford works to broker a deal between the two which would get his son and the prostitute out of town with ten thousand dollars to start a new life. But Ford isn't having it. He hatches a plan to kill the both of them, and, eventually, make off with the money. His plan, however, begins falling apart almost immediately, and he finds himself killing more and more to try and cover his tracks.
Michael Winterbottom does a great job of directing this thriller, based on a 1950's cult novel. Casey Affleck delivers, probably, the performance of his career, making you FEAR this small, understated man who is willing to do ANYTHING to cover himself. Winterbottom allows Affleck to go to wherever he needs to go, and does not hesitate to put every moment on the screen. The murder of Joyce is particularly graphic and disconcerting. I very rarely ever get sick, but this scene did nauseate me. Alba delivers, for once, an on par performance, but this isn't surprising, seeing as how the Joyce character doesn't really have too much to her. Alba's job is to, basically, wear practically nothing, look sexy, and make you want her. Like I said, not much of a stretch. A series of great acting in smaller roles also rounds out the film with Elias Koteas as a blackmailing Union rep, Tom Bower as the Sheriff of the little town, and Simon Baker as a Fed who is absolutely sure Ford is the killer, but has to find the evidence to prove it.