The small European population of the island of Mayou, off the coast of Papua New Guinea, is intrigued to see a yacht approaching the island. The two passengers appear to be respectable 'gentleman', but the trader Blount soon recognises the captain of the ship as one Captain Sykes, a notorious blackbirder who has served time in prison in Sydney for his activities. The chief of the island, Banderah, has his own grievance against Sykes and plots revenge. Blount uncovers a conspiracy between the visitors and the other two traders living on Mayou and he and Banderah devise a scheme to expose them. However, the plan goes hideously wrong and leads to bloodshed and death.