Colonial New Guinea, 1906. A small group of mostly German nudists live anextreme back-to-nature existence on the remote island of Kabakon. Eating onlycoconuts and bananas, they purport to worship the sun. One of their members, MaxLutzow, has recently died, allegedly from malaria. But an autopsy on his body inthe nearby capital of Herbertshöhe raises suspicions about foul play.Retired British military police officer Will Prior isrecruited to investigate the circumstances of Lutzow's death. At first, theeccentric group seems friendly and willing to cooperate with the investigation.They all insist that Lutzow died of malaria. Despite lack of evidence for amurder, Prior is convinced the group is hiding something.Things come to a head during a late-night feast supposedlygiven as a send-off for the visitors before they return to Herbertshöhe. Priorfears the intent of the "celebration" is not to fete the visitors—but to makethem the latest murder victims.