King of Devil's Island is based on a true story set in Norwegian winter, early 20th century. On the island Bastoy, located in the Oslo fjord, a group of delinquent young boys aged 11 to 18 live under a daily, sadistic regime run by the guards and the principal who subject them to mental and physical abuse.
Instead of receiving education, the boys are used as cheap, manual labor in an attempt to straighten them out. They must adapt to their inhumane conditions in order to survive.
One day, a new boy named Erling (17) arrives with his own agenda: escaping from the island. The film explores how far he is willing to go in order to gain his freedom.