In 1983 the author went to Peru to investigate the remains of the 500-year-old mummy of an Inca boy said to be the victim of human sacrifice. Later he discovered that human sacrifice is still practised in remote areas in the Andes. This book attempts to illuminate the significance of human sacrifice in man's social and religious development. Anthropologists and archaeologists are only now beginning to recognize that the ritual power to kill stands at the heart of many ancient societies and of much of our own cultural heritage - it is the mystery that unlocks the enduring enigma of Stonehenge, the complicated chain of high-altitude Incan shrines, Abraham's thwarted sacrifice of Isaac and even the crucifixion of Christ.