In 1936, a French man struck a pact that would turn his family home into a private laboratory for human endurance. Louis Didier persuaded a young mining couple to hand over their six-year-old daughter, Jeannine. He promised to educate her, feed her and bring her up, in return for the parents agreeing never to seek contact with her again. It was just the first step in an elaborate plan to father a superhuman child – one groomed to be able to survive the world's most abhorrent evils, from Nazi concentration camps to water torture. Jeannine grew up under Didier's control...