Horror in which a group of friends find themselves locked in a sauna where the temperature inexorably rises. Jenna (Scout Taylor-Compton), Renee (Christina Ulloa), Ian (Travis Van Winkle) and Michael (Michael Copon) head to stay at a remote lakeside cabin in high spirits. The cabin is owned by Ian's Uncle Wade (Tyler Mane), but when he takes off the youngsters are left on their own and decide to try out the cabin's sauna. Unfortunately, Michael has been drinking heavily and accidentally locks the other three inside the sauna. Jenna, Renee and Ian initially think they are on the receiving end of one of Michael's practical jokes, but as the clock ticks on and the heat becomes increasingly intense they realise they are facing a battle for survival. Will any of them be able to keep their cool as the temperature rises?