Last House on the Left-type revenge movie that has a serial killer murdering an entire family save two young women - though gory and technically competent, its really memorable part is an incredibly illogical plot twist lifted straight from Lost Highway. I'm certain the sexual relationship-as-metaphor came from seeing Miike and Murakami's Audition, but that twist added depth to the film - this turns it into a giant ruse (and am I correct in thinking the "unreliable narrator" is one of the cheapest 'tricks' in storytelling?). Come for the blood! Leave with confusion!
Director: Alexandre Aja
Year Released: 2003