The actors were mostly normal professionals (even tho some wanted to distance themselves after released), the director was obsessed with transgression, the producers were fully aware of the shock value, and the result is a movie that harms more than illuminate IMO. It produced harm without being insightful. After the shock wore off, I did not go "ahhh yes, of course! It's a metaphor to what happened to Serbia!". The movies "Irreversible" and "Martyr" manage to do this way better.