Tessa Quayle has been horribly murdered on the shores of Lake Turkana in Northern Kenya, the birthplace of mankind. Her putative African lover, a doctor with one of the aid agencies, has disappeared. Her husband, Justin, a career diplomat and amateur gardener at the British High Commission in Nairobi, sets out on a personal odyssey in pursuit of the killers and their motive. His quest takes him to the Foreign Office in London, across Europe and Canada and back to Africa, to the very spot where Tessa died.