A criminal suffering from lycanthropy is sent to a prison in Saturn where he has 62 moons to howl at. At the same time prison guard named Alex is preparing for his last shift before he heads back home before his wife gives birth to their first child. Two prisoners Michael and Dave are having hard times as they have been framed as the killers of gang boss in prison riot. When werewolf is set loose at the prison, fates of Alex, Michael and Dave are tied together when they try to survive the massacre and kill the werewolf before it will kill's every living person in the prison!