While digging a trench for a new water project, a backhoe operator unearths the skeleton of a long dead Bushman. Kubu and Scottish pathologist, Ian MacGregor, are sent to sort out the formalities, but the situation rapidly gets out of hand. MacGregor discovers eight more skeletons—a massacre of Bushmen including women and children. However, the locals deny any knowledge of the event. When an elder of the village is murdered at his home, the local police believe it was the result of a robbery gone wrong. Kubu thinks otherwise. So does an elderly woman who believes it was the work of Mami Wata, a powerful river spirit. When she dies in an apparent crocodile attack, suspicions rise. Things become still more complicated when a mysterious Bushman appears at the massacre site, collapses, then disappears again, but seems connected to the murders in some way. Kubu’s boss, Assistant Superintendent Mabaku, joins them as accusations of corruption are levelled at the water project, and international anger over the massacre of the Bushman families builds. But how do the recent murders link to the dead Bushmen? As they investigate, they uncover a deadly covenant made many years before by an unknown group, and they begin to fear that their own lives may be in danger.