tracing and examining the murder weapon. According to Pettersson's theory, the revolver was likely to have been one legally owned by an acquaintance of Engström's, an avid gun collector. The "Skandia man" theory had already previously been suggested by Lars Larsson in his 2016 book Nationens fiende (literally, "The enemy of the nation"), but this received only limited attention at the time. On 10 June 2020, the Swedish Prosecution Authority proposed The Skandia Man as the perpetrator and closed off the investigation since Engström is dead and can thus not be prosecuted, while noting the lack of direct evidence. Although Engström had a negative view of the prime minister, as well as long-standing financial and growing alcohol problems, investigators still did not have a "clear picture" of Engstrom's motive for killing Palme, Chief Prosecutor Krister Petersson said. Figures The cost of the investigation stands at SEK 350 million, €38 million or US$41 million . The total number of pages accumulated during the investigation is around 700,000. According to criminologist Leif G. W. Persson, the investigation is "the largest in global police history". The reward for solving the murder is SEK 50 million (approximately €5 million or US$7 million.) Film portrayals In the 1998 Swedish fictional thriller film The Last Contract (Sista kontraktet), Palme's assassination was portrayed as having been planned by a hired assassin. In the 2021 Netflix series The Unlikely Murderer, Palme's assassin was depicted as Stig Engström, the so-called "Skandia man," based on the book by Thomas Pettersson. Because Engström has never been found guilty in a court of law (having died in 2000 before the investigation was closed in 2020), the episodes' open with the words, "Based on an unsolved crime," and ends with the disclaimer, "It has not been proven that Stig Engström murdered Olof Palme, but the Swedish police and Prosecution Authority suspect him." See also Ebbe Carlsson affair List of unsolved murders Sources ; Leif GW Persson is a Swedish criminologist and, 9 years prior to the assassination, a member of the Swedish National Police Board. The book is the thinly disguised story of events leading to the assassination of Olof Palme. The book has Palme as having been a CIA agent in his days of student politics. Palme is mistakenly assumed by the American journalist who is killed at the start of the book to have later turned to work for the Soviets.