Turin, Vanchiglia neighborhood. On February 14, 1958 Mario Giliberti, 27 years old, disappears into thin air. Eleven days later he is found lifeless in his room on the ground floor of via Fontanesi 20: eighteen stab wounds, the body covered with a sheet, no sign of effort. Next, a disturbing ticket: “You will find the Assino”. From that moment they begin to get letters signed Diabolich: words games, encrypted messages, phrases written from right to left. A killer-enigmist who challenges police and public opinion. Almost seventy years later, the crime of Mario Giliberti remains one of the darkest and fascinating mysteries of the Italian chronicle. The complete analysis of the investigative journalist Alessandro Politi is online on this incredible case, with all the details and anomalies of a story that has not yet found an answer today.