Thanks to the glamorous scenes of James Bond, the image of an MI5 spy is a glitzy, charming and exciting one, but a new book sheds light on the eccentricity of the UK's top 'spymaster'.
The life of Maxwell Knight, known as the real-life 'M' who inspired the ruthless, yet admirable James Bond character has been revealed in Henry Hemming's new book, M: Maxwell Knight, MI5's Greatest Spymaster .
Mr Hemming told Get West London : "I was intrigued by his ability as a spymaster but also his eccentricity.
"He collected all sorts of unusual animals when he was younger and interestingly, it was his ability to look after and train these animals which helped him become such a successful spy.
"He became a very good judge of character because of this."
The mysterious 'M' recruited some of MI5's most successful agents, the majority of which were the first female spies, such as the notorious 'Miss X'.
Using his own detective work, Mr Hemming spent three years going through declassified MI5 documents and archives to identify Knight's protege, including the not so glamorous Marjorie Mackie, a stout, middle-aged single mother from Essex.
Mr Hemming said: "When he first got to MI5 most people said you shouldn't recruit female spies but Maxwell thought women made better spies than men.
"Most of his most successful agents were women and this set him apart.
"The other thing that set him apart is that he was so eccentric. He was obsessed with animals, jazz and wrote novels."
Knight spent more than 20 years living in Sloane Street, Knightsbridge in West London, where he surrounded himself with his wildlife collectables.
Mr Hemming said: "For a while he refused to work at MI5 Headquarters and ran operations from his flat, surrounded by his animals.
"When writing the scene of him surrounded by these unusual species, I was reminded of a combination of a John Le Carre novel with a Gerrell Derell scene."
Knight then returned to Surrey, where he "re-invented" himself into a "David Attenborough of his day".
In one decade he recorded 300 radio programmes, 40 TV episodes and wrote 20 books, all dedicated to his passion for animals.
Mr Hemming said: "During the war he had an MI5 safe house in Camberley, and later moved there with his third wife.
"He became a well-known and popular local figure, helping to set up the Camberley Natural History Society."
"All the while he continued his spy work until 1961. No one he met in Camberley knew about this - it was an amazing combination of jobs."
M: Maxwell Knight, MI5's Greatest Spymaster is now out in bookshops and a TV series is soon to follow.
Although the date of the series is yet to be announced Mr Hemming confirmed that it will be produced by the makers of 'Poldark' and 'Victoria' and written by Matt Charman, the award-winning screenwriter of Steven Spielberg 's Bridge of Spies.
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