Bomba knew with a sure instinct the reason for the presence of the headhunters of Nascanora, now far from their tribal abode in the shadow of the Giant Cataract. They were once more on the trail of Casson; Casson whom Bomba loved. They would try to capture him, take him to their village and torture him, and then, when death had brought an end to his sufferings, place his head on Nascanora’s wigwam.