Two men wake up at opposite sides of a dirty, disused bathroom, chained by their ankles to pipes. Between them lies a dead man loosely clutching a hand-held tape player and a handgun. Each finds a tape for the player in their back pocket. They play the tapes.

There is a timer on it. Only one key will unlock it, and that key is in the digestive tract of her cell mate who lies paralyzed on the opposite side of the room. If she doesn’t unlock the mask in time, her lower jaw will be ripped wide open.