a fictionalised account of Crabb's life, Man Overboard, that was published by Picador in 2005. Binding stated that, following the book's publication, he was contacted by Sydney Knowles. Binding alleged that he then met Knowles in Spain and was told that Crabb was known by MI5 to have intentions of defecting to the USSR. This would have been embarrassing for the UK — Crabb being an acknowledged war hero. Knowles has suggested that MI5 set up the mission to the Ordzhonikidze specifically to murder Crabb, and supplied Crabb with a new diving partner who was under orders to kill him. Binding stated Knowles alleged that he was ordered by MI5 to identify the body found as Crabb, when he knew it was definitely not Crabb. Knowles went along with the deception. Knowles has also alleged that his life was threatened in Torremolinos in 1989, at a time when Knowles was in discussions with a biographer. About the claims that Crabb was planning to defect to the Soviet Union, Reg Vallintine of the Historical Diving Society was quoted as saying: "Diving historians find it very hard to believe that this man, who prided himself on being a patriot, would have seriously considered defecting. Crabb was very fond of being a hero, and it is hard to imagine him jeopardising that status." It is not clear just why MI6 would recruit a man who was known to be planning to defect to the Soviet Union to spy against the Soviet Union or why Crabb would agree to such a mission if he really had decided that he wanted to live in the Soviet Union. Death by misadventure The British diving expert Rob Hoole wrote in 2007 that Crabb had probably died of oxygen poisoning or perhaps carbon dioxide poisoning, and that Crabb's age and poor health caused by his heavy drinking and smoking had made him unsuitable for the mission that he had been assigned. In support of the death by misadventure theory, Hoole noted that before disappearing on his second attempt to dive Ordzhonikidze, Crabb had during his first attempt experienced equipment failure, which suggested that Crabb's equipment was not up to standard. Crabb's MI6 officer Nicholas Elliott always took the view that Crabb had suffered equipment failure, or his health had given way, and that his reputation had been unfairly dragged through the mud. Historical media In a war documentary