Within (2005)

While traveling in Czech Republic, the American friends Brad, Christina, T.K. and Kelly find a map with the route to an ancient castle and they decide to visit the place. They force the entrance in the castle and after a while, they realize that they are trapped in the spot, without any exit and suffering painful hallucinations. When they meet the weird deranged Travis, the stranger explains that they are in hell, and one of them must stay behind to permit the rest of the group to escape. While they decide who will be the chosen one, the true nature of each one of them is revealed.