Madame de Trécesson, Marquise of Cavour and Charles Emmanuel II's favourite, roped the Duke into an episode so scandalous that it ended in murder. Apparently, a stable boy by the name of Cornavin happened by chance upon the secret passage connecting the Marquise's residence in piazza San Carlo to the nearby Palazzo Turinetti, home to guard officer François de Fleury... with whom the Marquise had an affair. The poor stable-hand paid dearly for his discovery, as his disfigured, lifeless body was later recovered on the banks of the river Stura. Charles Emmanuel, made suspicious by the murder of such a lowly worker, understood the truth behind it: he had the hitmen responsible captured and executed, condemned Fleury to a life in jail, and terminated his relationship with the Marquise.