In The Waters of Eternal Youth, the twenty-fifth instalment in the bestselling Brunetti series, our Commissario finds himself drawn into a case that may not be a crime at all. Brunetti is investigating a cold case by request of the grand Contessa Lando-Continui, a friend of Brunetti's mother-in-law. Fifteen years ago the Contessa's teenage granddaughter, Manuela, was found drowning in a canal. She was rescued from the canal at the last moment, but in many ways it was too late; she suffered severe brain damage and her life was never the same again. Once a passionate horse rider, Manuela, now aged thirty, cannot remember the accident, or her beloved horse, and lives trapped in an eternal youth. The Contessa, unconvinced that this was an accident, implores Brunetti to find the culprit she believes was responsible for ruining Manuela's life. Out of a mixture of curiosity, pity and a willingness to fulfil the wishes of a loving grandmother, Brunetti reopens the case. But once he start