The spoiler was on horrorphile... Apparently the "victim" murdered his captors daughter in the opening scene and the father is doing what he can to turn his daughters murderer into his daughter. Sex change operation, etc, etc, etc. Unfortunately this was pretty much given away in the trailer so all the crap about twists I was reading everywhere was probably viral marketing. Considering the movie doesn't have it's own wiki page but so many rave reviews around the place I should have guessed... Bit disappointing really, the "twist" is pretty much shown in the trailer.