Salò meets Rashomon, though the minimal docudrama approach plays more like a grindhouse variation on Peter Watkins. Although Boll does stumble across something quite brilliant in terms of his structure, with the contrasting stories of the participants creating doubts, suspicions and accusations that obfuscate the chain of events, the film is so explicit (bordering on unpleasant) that it's impossible to recommend.
My partner and I found this moving SO disturbing that we literally had to turn it off 50 mins in. I don't know if it is because it was so well captured or because you keep reminding yourself it is based on a true story. I found it beyond sad.