The auctioneer slammed his gavel, ending a 2018 bidding war at Sotheby’s in London. For $1.4 million, someone had bought one of street artist Banksy’s most iconic works: a silhouetted girl reaching for a red, heart-shaped balloon as it floats away.

Right then, the painting started beeping inside the packed auction house, and a secret shredder Banksy had built into the bottom of the picture frame whirred to life. Onlookers watched — eyes widening, mouths dropping — as “Girl With Balloon” slid down into its blades, slicing the bottom half of the canvas into dangling strips.

“The urge to destroy is also a creative urge,” Banksy wrote in an Instagram post after the event.

Art prankster Banksy shredded a framed canvas at a London auction on Oct. 5, 2018. Moments before, the artwork sold for $1.4 million. (Reuters)

On Thursday, three years after Banksy’s act of destructive creation, the anonymous buyer put up for auction “Girl With Balloon,” or rather, its successor — the retitled “Love Is in the Bin.” After nine bidders battled for 10 minutes, the semi-shredded artwork sold for $25.4 million. That’s more than three times the auction house’s top estimate going into Thursday’s auction and more than 18 times what the spray-paint-on-canvas creation sold for in 2018 when it was intact.

“It has been a whirlwind to follow the journey of this now legendary piece and to have it back in our midst, offering it tonight in the very room it was created by the artist,” said Alex Branczik, Sotheby’s chairman of modern and contemporary art.

The prank was “a brilliant comment on the art market,” London art dealer Acoris Andipa told the New York Times in 2018, adding that if he were the buyer, he would leave the painting in semi-shredded condition. “It‘s a part of art history.”

BBC News arts editor Will Gompertz called the stunt “brilliant in both conception and execution” in its indictment of the art world, one in which people aren’t disappointed that a piece of art was destroyed but concerned only with how that destruction has changed its value as an “asset.”

To highlight this, Gompertz said, Banksy staged “an attention-grabbing spectacle [the shredding] taking place within an attention-grabbing spectacle [the auction], which highlighted through dark satire how art has become an investment commodity to be auctioned off to ultra-wealthy trophy-hunters.”

“It will come to be seen as one of the most significant artworks of the early 21st Century,” Gompertz said.

The irony of the shredding, though, is that, instead of punishing a buyer looking to secure a Banksy by leaving that person with only a surprise heap of worthless tatters, it may have rewarded the purchaser with a far more valuable piece of art, Joey Syer, the co-founder of MyArtBroker.com, told the Evening Standard in the days after the first auction. Back then, Syer estimated the stunt could have added 50 percent to the artwork’s value.

Syer’s guess turned out to be far too conservative.

Over the past two decades, Banksy has grown into one of the most famous street artists in the world. The British graffiti artist, who’s maintained his anonymity over the decades, gained prominence through his many anti-establishment pieces, which he often paints secretly in public places. He has spray-painted two police officers kissing, one snorting cocaine off the ground, and several dressed in riot gear with yellow smiley faces. In 2019, his “Devolved Parliament” sold for $12.1 million — the Victorian-style painting depicted the British House of Commons filled with chimpanzees weeks before Britain was set to leave the European Union.

Early in his career, Banksy combined graffiti with performance art. In a 2003 exhibit, he painted on the bodies of live pigs. During another at a London gallery in 2005 featuring cheekily altered replicas of famous artists such as Claude Monet and Vincent van Gogh, he released 200 live rats in the gallery. That same year, he disguised himself so he could secretly install his own works on the walls of major museums in London and New York without getting caught.