The Ushiromiya family makes an annual pilgrimage to Rokkenjima, the island where they gather for a reunion hosted by the odd patriarch, Kinzou, who is in poor health. The family members are preoccupied with feuding over the inheritance and the coveted title of Kinzou's successor. A typhoon outside matches the turmoil brewing in their hearts as they argue.
Battler, Kinzou's grandson, returns after a long absence expecting a smooth reunion. But Kinzou has different plans; he introduces a peculiar game which involves finding his hidden treasure. The victor will become the family leader. However, the game turns grim as participants are used as "sacrifices" to bring back the Millennial Witch of Rokkenjima, Beatrice. Murders and violence ensue, casting doubt on whether the work of magic or the acts of one of the family members.
Despite the ensuing disasters, Battler remains skeptical of the occult, questioning what truly happened to those closest to him.