The best-selling true story of how an American crime writer was sucked into the long-running and bizarre police investigation of Italy's worst serial sex killer is to become a Hollywood film, produced by Tom Cruise.
The Monster of Florence by Douglas Preston and Mario Spezi tells how Mr Preston, a successful writer of crime novels, travelled to Florence and moved into a beautiful old villa on the city's outskirts.
Mr Preston's plan was to write a murder mystery set in Florence at the time of the great flood of 1966. It was to be entitled The Christmas Madonna and feature an American art historian who rushes to the city to help dig it out of the mud. In the process he finds a clue to the whereabouts of a celebrated missing work by Masaccio, the painter who launched the Renaissance. But when he sets off in pursuit of the painting, he ends up being horribly murdered.
Mr Preston realised he would need to understand the workings of Italian murder investigations if his book were to ring true, and a mutual friend put him in touch with Mr Spezi, a crime reporter who for more than 20 years had worked the cronaca nera desk ("black story" or crime beat) at La Nazione, the daily paper of Tuscany and central Italy. The two men met in a Florence café, and when Mr Preston told Mr Spezi he was living in Giogoli, "Spezi's eyebrows shot up".
Mr Spezi was Italy's greatest expert on the "Monster of Florence", the serial killer armed with a .22 Beretta pistol who preyed on courting couples in their cars in quiet lanes outside the city, killing 16 of them between 1968 and 1985 and hacking off and carrying away the women's vaginas – a gruesome detail which Thomas Harris borrowed for his novel Hannibal. Mr Spezi had coined the term "Monster of Florence" and it transpired that Mr Preston had rented a villa overlooking the site of one of the Monster's murders.
All thought of The Christmas Madonna was forgotten as Mr Preston became fascinated by the case. For the monster's crimes had never been solved: one man who was convicted and jailed was later released on appeal. Like Mr Spezi, Mr Preston came to believe that the police had failed to pursue the most promising leads and the pair began some amateur police work of their own.
But in the process they drew the ire of the latest investigators, who hauled Mr Preston in for questioning and threw Mr Spezi in jail, putting him under investigation on suspicion of trying to derail a criminal investigation – and also on suspicion of being the Monster himself. Three weeks later he was released, the Supreme Court declaring his imprisonment "illegal and destitute of any foundation". But Mr Preston was warned that he could be re-arrested if he set foot in Italy again, and left the country, never to return.
Tom Cruise was gripped by The Monster of Florence, which sold 300,000 copies in the US. When he met Mr Spezi at the Italian premiere of Valkyrie in Rome in January, he told him his character would be the star of the film. "I met Cruise with Christopher McQuarrie, his screenwriter," said Mr Spezi. "Tom said they weren't interested in making yet another film about a serial killer but were fascinated by the story of how two writers got caught up in the investigation and suffered the consequences."
If the film stays true to the book, it will lift the lid on many disturbing aspects of Italy's justice system, in particular the willingness of police and prosecutors to put their trust in bizarre sources of information – and then to punish and persecute the rare journalist like Mr Spezi who refuse to kowtow to them.
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It was in 2002 that Michele Giuttari, the latest detective to head an investigation into the Monster's killings, exhumed the body of Francesco Narducci, a doctor from Perugia who had drowned in Lake Trasimeno in 1985. Apparently acting on a lead provided by Gabriella Carlizzi, a psychic who claims to be fed information by a long-dead priest, the public prosecutor of Perugia, Giuliano Mignini, persuaded Mr Giuttari that Mr Narducci had not committed suicide but had been murdered by important Florentines because they, like Mr Narducci, were involved in Masonic rites which centred on the Monster's murders.
There was not a scrap of evidence for this story, but this did not prevent the investigation from going ahead.
Mr Spezi made no secret of the fact that he regarded the Narducci theory as bunkum. But when he and Mr Preston began exploring the long-abandoned investigation which they believed would have led police to the true killer, Mr Mignini, who is also the prosecutor in the Meredith Kercher murder case, and who is separately fighting charges of abuse of office, came down on them hard.
Mr Preston is out of harm's way, but the judicial persecution of Mr Spezi by Messrs Mignini and Giuttari continues apace.
"They accuse me of being the mastermind or instigator of the murder of Narducci," Mr Spezi said wearily. "Now it's more than an investigation, I have actually been charged with the murder; also with forming a criminal association to cover up the crime (along with 23 other people in Perugia); with obstruction of justice, with perjury, and with criminal libel against Giuttari, Gabriella Carlizzi and others. I am indicted for writing articles that 'disturb public order", because I criticised the investigation in Perugia regarding the murder of Meredith Kercher, and I am also accused of 'vilifying' prosecutor Mignini, a criminal offence.
"I have the strong impression that I will never get out of this situation and I don't know what to do. Everything I do causes Mignini to accuse me of another crime."
Mr Preston commented: "It seems extraordinary that even after the Italian Supreme Court ruled that Mignini's detention of Spezi was illegal, Mignini is still persecuting him relentlessly, without any kind of check or control. Mignini himself is on trial for abuse of office – yet he continues in office as if nothing were happening. The Monster of Florence is not just a book about a horrific serial killer, and not just a book about two journalists who fall into their own story. It is a book about modern Italy itself.
"Mario and I are confident that the story we tell is the truth, at least as far as the truth can be ascertained in a strange and convoluted case such as this. But this has not stopped the Italian authorities from levelling vague charges of criminal libel against us, not because there are errors in the book, but for harassment purposes and to undermine our credibility. Our aim was to tell the truth, and we told the truth – at a far greater cost than we anticipated. As a result, I can probably never return to Italy and Mario spent three weeks in prison and may be persecuted to the end of his days. But we both stand by what we wrote."
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