 The sole time he was successfully prevented from claiming a mortal life was by the intervention of the hero Heracles, a son of Zeus.Thanatos had come to take the soul of Alkestis, who had offered her life in exchange for the continued life of her husband, King Admetos of Pherai.Heracles was an honored guest in the House of Admetos at the time, and offered to repay the king's hospitality by contending with Death itself for Alkestis' life.