A not very banal history in a rather macabre frame. Why these anonymous letters, why these two murders around Carrington, the inventor of the sophisticated prosthesis? A rival business company, which wants to monopolise the market of the artificial members, is suspected of having an accomplice in the place. Meanwhile, Carrington uses its own daughter as guinea pig... All things considered, a nice history of pity and of hate. Pierre Boileau and Thomas Narcejac wrote a work which makes its mark in the history of the detective story and that, from Clouzot to Hitchcock, often inspired the film-makers: The Diabolic, The she-wolves, cold Sweats, The faces of shadow, Murder in 45 turns, The sorceresses, Bewitching, Misdeal...