The Killer Inside Me

The Killer Inside Me places the viewer totally inside the viewpoint of psychopathic deputy Lou Ford. In the novel, this was done via first person narration. The film makes use of sporadic voiceover but mainly achieves the effect through Ford's presence in almost every scene. The viewer sees and knows what he sees and knows (the handful of scenes where he's absent arguably show actions that he can imagine: Conway asking his driver to take him to the hospital; Amywalking to his house; the lawyer bulldozing his way down the asylum corridor) There is no other POV, only Ford's interpretation of the world around him. We never see the point at which Bob realizes the extent of his deputy's crimes, nor any of the machinations conducted by Conway or the DA. Most importantly, we *never* see how Joyce and Amy truly feel about him, only his projection of their pathetic devotion to the man who brutalizes them. The only occasion the film shifts perspective is near the start (in Joe's office and later on the night of the first crime) and it's done subtly, via a change in framing and a bit of handheld camerawork. It's also a crucial bit of information for the viewer to file away for later use.
As for the already notorious violence - especially the attack on Joyce - it's mostly done through blocking, editing and judicious makeup. We hear the blows slamming into Joyce but don't see them (although we think we do). It's a deeply distressing scene: for the violence and for the revelation of Ford's shocking coldness. He plans his murders calmly and commits them without the slightest shred of mercy or conscience. He willingly sacrifices others for his own ends, though bizarrely, he never seems to contemplate killing Joe who represents the biggest threat, while Joe himself never seems to fear for his own safety. In fact he even provides the lawyer who gets Ford released from the asylum. Perhaps they recognize oddly kindred souls, though with Ford's slippage between sanity and madness that's not a comforting thought.