The Monster of Florence killed sixteen people in eight double murders in the countryside around Florence. In every case a young couple was found shot in a parked car in a quiet lane at night, and in most of them the woman's body had been mutilated after death, with parts removed. Every shot fired across seventeen years came from the same Beretta .22 pistol, loaded with Winchester series H ammunition.
The first, in August 1968, was the killing of Barbara Locci and Antonio Lo Bianco at Signa. Locci's husband, Stefano Mele, was convicted of it. The gun then reappeared in 1974 at Borgo San Lorenzo, and again in 1981, 1982, 1983, 1984 and finally in September 1985 at Scopeti, where two French tourists were killed in a tent.
The investigation is one of the most criticised in modern Italian history. Prosecutors pursued a Sardinian clan theory, then a satanic cult theory, then a theory involving a wealthy conspiracy commissioning body parts. Pietro Pacciani, a farmer, was convicted in 1994 and acquitted on appeal in 1996; he died before a retrial. Two associates, Mario Vanni and Giancarlo Lotti, the compagni di merende, were convicted as accomplices. A doctor, Francesco Narducci, was posthumously worked into the cult theory, and the prosecutor who pursued it was himself later convicted of abuse of office. Douglas Preston, who wrote about the case with the journalist Mario Spezi, was interrogated as a suspect and Spezi was jailed.
Nobody has been convicted of the killings themselves in a verdict that survived. The gun has never been found. The case remains open.