Just outside David Henty’s lovely seaside home in Sussex there is a blue plaque stating “The world’s number one art forger — he has painted more Lowrys than Lowry”.

Do you think that’s true, I ask him. “Well, I have painted a lot. I painted three little ones yesterday.”

Henty, 65, is not just focused on LS Lowry, the 20th-century British artist known for capturing life in the north. He also does works by Monet, Modigliani, Caravaggio, Basquiat, Sickert … the list goes on. He both forges and copies them. There is a difference. As he puts it, a Mona Lisa he has upstairs in his house is a copy because it is a direct replica. Whereas if he painted a new scene using Leonardo’s style, that would be a forgery.

Authenticity is tricky to achieve but Henty has many tricks up his sleeve: using the right canvases and boards (sometimes hundreds of years old), priming them with lead white so they can’t be X-rayed, finding old organic paints, adding amber to make them darker, keeping paintings in a smoker’s house and more. He also sometimes leaves paintings out for weeks so they develop cracks, or bakes them in the oven. “At a low heat: 80 to 100 degrees,” he details. “It does smell, so you’ve got to have the windows open. My wife doesn’t like it.” This he says with a laugh. He loves to chuckle and does so a lot during our conversation in his garden, which serves as his studio when the weather is nice.

“Some of my clients, you can’t believe how rich they are,” he tells me. There are football club owners and managers, political figures (he won’t tell me names). Galleries up and down the country sell his work and his commissions fetch up to $61,000. One man in Monaco offered to fly Henty over in a private jet to make a copy of a $8.5 million Picasso he had just bought. “He’s got some young children and didn’t want it damaged.” So he wanted to put the real one in the bank and have Henty’s in the front room. Hedge funders in charge of masterpieces do the same — leave them in a vault and order copies from Henty. And sometimes his old forgeries reappear in auctions as the real deal: in 2019 a Picasso he had painted was valued at $1.2 million before he came forward and said it was his.

A character in Peter James’s novel Picture You Dead is based on Henty, as is one in a film script by the actor Nick Moran (of Lock, Stock and Two Smoking Barrels fame). Henty himself has written a book with a friend about forgery, called Art World Underworld, and has been in documentaries and on the radio. Museums ask for his help, as do TV producers when they need a painting. Now he is doing an event at the London Design Festival.

“I’m really proud. Me and my brothers, we laugh because we can’t believe it,” Henty says of his successes. “I have to pinch myself.”

He also sometimes leaves paintings out for weeks so they develop cracks, or bakes them in the oven.

Because it certainly has not always been smooth sailing. He was permanently banned from eBay and got in trouble with the taxman. Once, he says, after admitting one of his paintings was a forgery he received arson threats from interested parties and had to install cameras in front of his house. Also he has been imprisoned twice, first in the early 1990s and again in the early 2000s.

David Henty “has painted more Lowrys than Lowry.”

Born and bred in the Brighton area, he left his local comprehensive at 16 and never went to any university or college, and says: “I wasn’t very good in school.” But he was always drawing. He would copy images from books: Michaelangelos, Hogarths. “I just could always do it … this is the funny thing about art. I always thought everyone could paint. I never thought it’s anything special. I could just knock out a Picasso.”

“I come from an artistic family,” he says. His sister Shani Struthers is an author, two of his brothers also paint and draw, and the other two are in antiques, as was his father, Tony. “My dad was dodgy,” Henty says with another of his laughs. “He used to forge jewelry and silver and stuff.”

Henty spent his twenties “ducking and diving” and selling antiques. Then, in 1989, he got in trouble with the law. In the lead-up to the handover of Hong Kong to China there was demand for fake British passports and some of Henty’s friends were offered $3.6 million if they produced a thousand. They enlisted him to help because he knew how to do watermarks and embossing. But after only a few months they got caught — spelling was one of the clues that gave them away. They wrote “magesty” instead of “majesty”.

He served more than two years with stints at different prisons including Highpoint. “It was a nightmare,” he says. Painting, however, gave him respite. He went to art class and made friends with the teachers. “I was the only one allowed to take my paintings back to my cell because I was really enthusiastic … in the prison studio we had Van Goghs, Monets, you name it hanging up.” When he saw photos of a local Sickert exhibition in the newspaper he painted them. Hours were also taken up with researching artists, sitting in the library reading about them. “My time flew … when you’re painting or doing something creative you’re away with the fairies.”

The second time Henty went to prison it was for selling stolen cars using (you guessed it) forgery via a fake Irish logbook. Was he not scared about being caught again? “We didn’t really think it through,” he says. “We were making $48,000 to $61,000 at a time and we thought, this is great.” He bought a nightclub, drove around in sports cars wearing Rolexes. “The police became suspicious,” he says, and he was locked up for another 18 months.

“Some of my clients, you can’t believe how rich they are.”

A year of this stint was spent in Spain, where he had been arrested. “There was a lot more freedom than in English prison — you’re open all day.” Many international prisoners were, like him, waiting to be extradited, including an Italian mafioso called Vincenzo he befriended through art. “He was trying to paint his wife and he was doing a terrible job,” Henty remembers. “I painted his wife and kids and we got on really well.”

Henty always liked doing portraits, especially of famous artists and boxers. But they took longer and never made much money when he tried to start selling them on eBay. Then one day in 2008 he put up a forgery of his and received $854. “It was such a nice living,” he says. “I’d knock up a Paul Henry in the afternoon on an old canvas and get £1,000 [about $1,200].” A solicitor he went to for advice on how to sell without getting arrested said as long as he put a caveat in the adverts saying it was “after” or “in the style of” an artist, and he had no paperwork or provenance, he would be fine. Henty went on for years as the eBay forger “David Diamond.”

Henty’s forgery of Vincent van Gogh’s Café Terrace at Night.

In 2014, however, eBay shut down his accounts when The Sunday Telegraph did an exposé on him and he had to stop, at least temporarily. In reality he just changed his IP address and set up new ones. Then the paper did another exposé on him a year later. “I was devastated,” Henty says of losing his eBay income again. “I’m sitting there and thinking, what am I going to do now?”

He got over the upset in the end. “I’m quite fortunate in my life, I’ve had some good luck.” A $12,000 commission came through the post from someone in Ireland. Then he did an exhibition in Brighton that sold out, and more and more requests started rolling in. Pieces in his own style priced at more than $36,000 are also now shown in a gallery, as part of a project he is doing with his friend Jake Fern called the Righteous Brothers, where they paint satirical works of social commentary, criticizing Sadiq Khan or the King. Next in the firing line is Jeremy Hunt.

He has been imprisoned twice, first in the early 1990s and again in the early 2000s.

His house is filled with canvases of all genres, hanging or piled up, antique gilded frames he buys by the vanful from a friend in France, and art catalogues. Aside from going to multiple exhibitions here and abroad, he likes to “soak” himself in an artist, read and watch everything available about them. “Then what happens is because your subconscious has taken so much in, you start dreaming you’re Caravaggio,” he says. “You go to start working and it’s almost like you click over and you’re painting away, you’re in the zone.” He paints left-handed for Caravaggio, as well as for John William Waterhouse.

Henty is a man of theatrical details. A lot of his reference books are in his “forger’s den,” a little nook hiding behind a fake bookshelf under his stairs, and he discusses new techniques with his forger friends, especially one he calls Billy the Brush. His licence plates are variations of V 90GH in tribute to the Dutch great. Old forgery stories also thrill him — he talks to me avidly about the late Tom Keating as well as Eric Hebborn, who in 1996 died in mysterious circumstances in Italy.

There are styles Henty has not been able to imitate. “I had a commission for a Frida Kahlo and I just couldn’t get her,” he says. “I just couldn’t work her out.”

And there are those who criticize what he does. “If you don’t want to buy it, don’t buy it” is his attitude. “I don’t care. I just like doing it. This is my passion.” He wears a T-shirt with a spin on Picasso’s famous saying “Good artists copy, great artists steal, David Henty does both!”

Suddenly last year he had a huge scare when he was diagnosed with pancreatic cancer. “You just think, well, that’s it, it’s over. Because not many people recover from it.” He is now in the clear, though it took an 11-hour surgery and a long recovery, during which he got sepsis. “I couldn’t paint, I couldn’t get up for months,” he says, adding that he still has to rest a lot. “But now I’m back working and loving life again and thinking, I’m so happy to be here and doing what I love. Because I love my job. I don’t want to do anything else.”

Blanca Schofield is the assistant arts editor at The Times of London