At the beginning of the 20th century on the island of La Réunion, five adolescents of good family, enamored with the occult, commit a savage crime. A Dutch Captain takes them in charge for a repressive cruise on a haunted, dilapidated sailboat. Exhausted by the methods of the Captain, the five boys prepare to mutiny. Their port of call is a supernatural island with luxuriant vegetation and bewitching powers.