There are some people in a house, I remember some being Asian if not all, and they have their own rooms where they find a clue per person. They shouldn't come out at night , one guy did and his head was cut by a mechanical circular rotating blade I think. People die one by one and they find these cameras and realise they are on a game show. There is a locked door in the house which somebody opens later and the bodies are buried there and have the same number of holes dug up as the number of people there. I think it was a foreign language film, Japanese or Korean but I'm not sure.