Charles Hill isn’t an easy man to trace. ‘I have made some enemies,’ he says with wry understatement, as we stroll through the wintry anonymity of Richmond. ‘Discretion seems like a good idea.’

Mild-mannered, of academic mien, Mr Hill doesn’t look the kind of man to have upset members of the criminal underworld. But after more than 20 years as Britain’s premier art sleuth, finding works by artists such as Goya, Munch and Titian, there are those who don’t wish him well.

‘My greatest thrill was finding Vermeer’s Lady Writing a Letter with her Maid, which was stolen from Russborough House in 1986 by Martin “The General” Cahill,’ he says, referring to the infamous Irish mobster. ‘Seven years later, I put on a mid-Atlantic accent and posed as an art dealer who had Arab buyers lined up for the Vermeer. At the time, I was working in Scotland Yard’s Art Squad. I was taken to a multi-storey car park in Antwerp by a gangster, and had to mask my emotions as I unwrapped the painting. It’s the greatest masterpiece I’ve had the pleasure to hold.’

It was with the 1994 theft of Edvard Munch’s The Scream from the National Gallery in Oslo, and the BBC’s documentary about its recovery, that Mr Hill first came to wider public attention not, for obvious reasons, by name. ‘Two men with a ladder simply smashed a window and made off with one of the most recognisable paintings in the world,’ he laughs. ‘They were in and out in less than a minute. That was organised crime, Norwegian style.’

Embarrassed, the Norwegian government enlisted Scotland Yard. ‘I posed as a representative of the Getty Museum, wanting to buy the painting. The Getty was wonderful in creating an identity for me. There was a lot of tough talk and near misses, but the thieves including the Scandinavian kick-boxing champion fell for it. We settled on £400,000 in kroner, although we’d been prepared to pay up to $5 million.’ In the event, the thieves were released on appeal, as the sting was deemed illegal in Norway.

A loner with maverick tendencies and a fierce intelligence, plus a low tolerance for bureaucracy, Mr Hill radiates Morse like insubordination, as well as the charm. ‘If Prince Valiant and Philip Marlowe shared custody of a single body,’ says Edward Dolnick, who wrote Stealing the Scream, ‘the result might resemble Charley.’

Born in Cambridge in 1947 to an American airman father and a British ballerina mother, Mr Hill excelled academically. At the age of 19, he volunteered for Vietnam and served as a paratrooper. Two years later, he went to study history at George Washington University, where he paid his way by working nights as a security guard. ‘But never on a Saturday. I had a season ticket to the Washington Symphony. I believe you gain a better understanding of history through culture.’ He won a Fulbright Scholarship to Trinity College, Dublin, before attending King’s College, London, to read theology. He then joined the Metropolitan Police as a bobby on the beat, and rose to detective chief inspector. ‘I never made it to superintendent: they said I was overly focused on crime.’

Since 2002, Mr Hill has been a free agent, offering security advice, and retrieving stolen art
Lord Bath’s Titian, Rest on the Flight into Egypt, being among his recent triumphs. It suits him well. ‘I no longer do undercover work. It’s too dangerous.’ Instead, he elicits vital information by cultivating the bad guys. ‘Yesterday, I had a meeting with the head of a crime gang about the where-abouts of some missing treasures. He’s a brilliant source of information.’ Mr Hill is adamant he never pays ransoms, only rewards ‘they’re quite different. I would not deal with a thief or his initial handlers. But paintings change hands quickly, and you soon enter a grey area’. Sometimes, paintings find their way into the system. More often, they’re sold to other criminals for a fraction of their worth to fund drugs or arms, or are stashed away as bargaining tools, in case of capture. ‘I’m sure that when James “Whitey” Bulger [a criminal on the FBI’s 10 Most Wanted list] is finally caught, the Vermeer and Rembrandt stolen from Boston’s Isabella Stewart Gardner Museum will resurface.’

Has he ever failed to retrieve a painting? ‘Never,’ he grins. ‘But that’s because I never give up. Those cases just remain open, until they’re solved.’

To contact Charles Hill, email hillartrisk@aol.com. Mr Mould’s book ‘Sleuth: The Amazing Quest for Lost Art Treasures’ is published on June 1 by Harper Collins