For true connoisseurs of the unexplained … nothing is perhaps quite as tantalizingly baffling as the story of Pier Paolo Pasolini’s last, unfinished book, Petrolio. After the poet, novelist and film director was murdered in 1975 – and the reasons for his death are themselves a mystery – it was found that Pasolini had left a manuscript running to more than five hundred pages. It was divided into numbered sections the author called Appunti (‘Notes’). The central figure in Petrolio is a man (who turns into a woman halfway through) working for the state-owned oil and gas company, ENI. The book was not published until seventeen years after Pasolini’s death, by which time one of the Appunti – number 21 – had disappeared. Pasolini’s family has always denied it was stolen. But there has long been speculation that Appunto 21 was made to vanish by someone because it contained embarrassing revelations about ENI and/or its executives. One theory is that the missing section contains the key to the death in 1962 of the corporation’s swashbuckling boss, Enrico Mattei, who was killed in a plane crash. Another hypothesis is that the disappearance of Appunto 21 has something to do with the fact that Pasolini owned one of the very few copies of a pamphlet that claimed to reveal secrets about a later ENI president, Eugenio Cefis. The pamphlet disappeared from circulation immediately following its publication in 1972.

In 2010, thirty-five years after Pasolini’s death and eighteen years after the publication of his strange, unfinished work, another hugely controversial – and inscrutable – figure, Marcello Dell’Utri, dropped a bombshell at a press conference ahead of the opening of that year’s antiquarian book fair in Rome. Dell’Utri, a bibliophile, advertising executive, politician and close associate of the former prime minister Silvio Berlusconi, said he had been offered part of the manuscript of Petrolio, prompting excited speculation that the typewritten sheets he had seen included the missing Appunto 21. Dell’Utri said he would put the pages on display during the book fair. But he never did. The only explanation he gave was that ‘The person who promised them to me disappeared.’