After swerving out of his little Chelsea square, James Bond “pushed the car fast up Sloane Street and into the Park”. And with that clue, one of the spy world’s biggest secrets may just have been cracked.

The author William Boyd claims that he has pinpointed the house where the spy’s creator Ian Fleming placed his character when 007 was able to enjoy some home comforts, which happens to be a few car lengths away from where John le Carré placed George Smiley, Britain’s other great fictional spy character of the 20th century.

While preparing for his Bond continuation novel Solo, which was published in 2013, Boyd re-read all Fleming’s novels, partly in search of clues about which Chelsea street had been chosen for his hero’s home.

In the forthcoming edition of the Times Literary Supplement, Boyd writes that Moonraker, Thunderball and From Russia with Love had provided the crucial clues. In Moonraker, for example, Fleming refers to Bond’s home as a “comfortable flat in a plane-tree’d square off the King’s Road”.

Sean Connery with Ian Fleming on the set of Dr. No in 1962.

There are several squares like this, Boyd writes, but “Fleming lets slip a crucial co-ordinate” when in Thunderball he has Bond swerving out of the square into the King’s Road and then “fast up Sloane Street and into the [Hyde] Park”.

The proximity to Sloane Street, routes to Hyde Park and the presence of plane trees left one candidate: Wellington Square.

The square has previously been identified by 007 Kremlinologists with a spoof biography of Bond by John Pearson in 1973, identifying No 30. However, this had been a private joke by the biographer, whose university friend lived at the property.

Moonraker, Thunderball and From Russia with Love had provided the crucial clues.

The more plausible address, Boyd writes this week, is No 25, which belonged to Desmond MacCarthy, a leading light in the Bloomsbury Group who would have been the chief book reviewer at The Sunday Times when Fleming was the newspaper’s foreign manager. Fleming was also friendly with Cyril Connolly, a protégé of MacCarthy.

Two other clues were found in From Russia with Love, in which Bond’s home is described as having a “long, big-windowed sitting room” which is “booklined”.

“The circumstantial evidence is compelling,” Boyd writes, adding that MacCarthy and his wife, Molly, were “legendary entertainers and their home became a kind of salon”. He adds: “It is highly probable that Fleming went to one or more of the MacCarthys’ parties.”

And then there are the references in the novels to authors including Eric Ambler, John Milton, Ralph Waldo Emerson and Edgar Allan Poe.

“Most readers wouldn’t think of James Bond as an intellectual,” Boyd writes, adding that Fleming “took pains to stress Bond’s wide reading, despite the fact that Bond had no tertiary education … Bond is a very well-read spy. I would argue that this is another spin-off from Fleming’s location of Bond’s flat in Desmond MacCarthy’s house.”

Boyd writes that given Smiley was in the nearby Bywater Street, “we can imagine Bond and Smiley as near neighbors for a good few years … when Bond swept out of Wellington Square in his Mark II Bentley Continental he might have passed the bespectacled, portly figure of George Smiley heading for the Tube station in Sloane Square on his way to Cambridge Circus.”

The Wellington Square house remained in the MacCarthy family until last year when the grandson sold the property to Frank Cordes and his wife, Iride Rosa.

The couple told The Times yesterday that they had been drawn to it because of its connections with the Bloomsbury Group. “I am a huge James Bond fan,” Mr Cordes, a managing director and partner of Boston Consulting Group, said. “I thought this might be my ticket to an Aston Martin but it is the mortgage that will probably stand between me and that car.”

Ms Rosa, an architect, was still more excited by the Bloomsbury Group connections. “I am more of a Virginia Woolf fan,” she said.

Sean Connery as James Bond in Thunderball, 1965.