Deep in a tropical jungle, Professor Forrester and his assistant discover a stone with both magical and primitive power. With it they can become masters of the world. But it does not bring them happiness - his assistant dies and the Professor mysteriously disappears while looking for a doctor. The mysterious disappearance of the Professor, the death of his assistant and the existence of the stone attract from a number of parties - not all of whom are what they seem. First of all, Lord Kingsley of Scotland Yard appoints his top agent Jane to find the Professor; she is joined by Rex Forrester and they leave for Akasava to look for the Professor. In Akasava Doctor Thorren and his wife run a practice for local natives. Thorren cannot explain the disappearance of the Professor; however he seems to know more about the stone. Thefts, muggings and murders are committed, as the various parties hunt for the stone. Rex admits to Jane that he is not related to the Professor, but like her a secret agent. Together they locate the mastermind behind all the plotting, and seek to take him to London and to justice. But before they can do that, in the lust to posses the stone and its powers, another will die a horrible death - the final victim?