It was a unique restaurant in London and certainly the hardest to get into. And it beat out thousands of upscale restaurants in the city to earn the top ranking on the popular review site TripAdvisor for a time, drawing a flood of interest.

There was just one small problem: It didn’t exist.

The restaurant was just a listing created this year by freelance writer Oobah Butler as an experiment on TripAdvisor, where his home — a shed in the Dulwich area of South London — suddenly became a high-concept new restaurant: The Shed at Dulwich.

With hardly more than some fake reviews — “Best shed-based experience in London” a particularly cheeky one stated — and a website, it had gamed the site’s ratings in London — a highly sought after designation that could bring a surge of business to any restaurant, let alone one in a major global capital.

The story has travelled around the globe and back after Mr Butler wrote a piece that exposed the ruse on Vice.

It has been hailed as an incredible feat. But in an era increasingly influenced by disinformation online, it also has served as another reminder of the ease with which pranksters and other dishonest actors are able to game online platforms to sometimes unthinkable results.

Mr Butler’s tale begins with an idea he developed after a past gig writing fake TripAdvisor reviews for restaurants: that the site was a “false reality”, despite the millions of comments left by honest reviewers.

So he wrote that in the “current climate of misinformation”, he decided to see how far he could take a fake restaurant on the site.

He created a listing for the garden shed that he lived at in Dulwich and “The Shed” was born.

Mr Butler, who did not respond to a request for comment, began taking the steps to ensure that the restaurant would be approved to be listed on the site. He bought a burner cellphone to serve as the restaurant’s phone number. He created a web page with a menu based off emotions — a concept “silly enough to infuriate your dad” — and illustrated it with photographs of arty-looking dishes made of household products like bleach tablets and shaving cream. One photo showed an egg on a plate balancing gracefully off his foot, which was cropped out of the frame.

Camera Icon Arty-looking dishes were made of household products like bleach tablets and shaving cream. Credit: Sunrise

And he listed its location as the street he lived on with no address, calling it an “appointment-only restaurant” to make himself less vulnerable to fact-checkers and would-be customers.

Exclusivity? Check.

And then, Mr Butler wrote, the first miraculous thing happened: It was approved by TripAdvisor to be listed in May. The restaurant started out as the 18,149th ranked restaurant in the city: dead last.

So he began having family and friends flood the site with fake but real-seeming reviews.

“Spent a weekend in London and heard through the grapevine that this place is a must-visit,” one chimed in. “After a few mildly frustrating phone calls, I was in.”

Some reviewers included some vaguely unsavoury details seemingly meant to enhance their credibility: one wrote about being offered a blanket with a stain, but still gave the restaurant five stars. Out of the 104 reviews left on the site by early December, more than 100 were for five stars, its top rating. The remainder? Four stars.

Soon enough, the customers started calling. Mr Butler captured some of his conversations with them on speakerphone in a video. “We are fully booked,” he tells the would-be diners. He played up the restaurant’s mystique, asking some if they knew “Jackie” and others about how many Instagram followers they had.

It didn’t matter, no one got a reservation. But the restaurant’s stock started to rise in TripAdvisor’s rankings.

“I realise what it is: the appointments, lack of address and general exclusivity of this place is so alluring that people can’t see sense,” Mr Butler wrote. “They’re looking at photos of the sole of my foot, drooling.”

The Shed’s phone continued to ring. By the end of August, the listing had climbed to number 156, Mr Butler wrote.

Others began to notice. Some companies used an estimated location of The Shed on Google to send free samples to him, he wrote. People looking to work with him started contacting him. And then the local governing council inquired about relocating them to a new development site, he said.

After the restaurant was ranked 30th, reservation inquiries started coming in from around the world. Some tried to find the restaurant in the real world. “People approach me on my road to ask if I know how to get to The Shed,” Mr Butler wrote. “And the phone rings more than ever before.”

And then he said he received a note from TripAdvisor, expecting to hear that he had been exposed: Instead the company told him that his listing received 89,000 views in a single day, he said.

The Shed at Dulwich had ascended to the No.1 ranking on TripAdvisor in all of London.

It was not an insignificant achievement. A top rating on TripAdvisor in a destination city such as London can bring a windfall of customers.

The website is the most visited tourism resource on the web in the United States, according to analytics firm SimilarWeb.

TripAdvisor’s American and British sites receive about 200 million visitors a month, according the firm’s estimates.

The story is incredible enough to merit a healthy dose of scepticism.

But images of TripAdvisor’s homepage for restaurants in London saved by the Internet Archive show its climb to the No.1 ranking by the first week of November.

It reached No.21 on November 2 after a reviewer called it the “absolute champion”, then No.3 the next day after two people wrote “worth the wait”, and finally took the vaunted top slot on November 4 after more reviews brought it across the line. It appeared to stay there for days, showing up as No.1 through November 8.

TripAdvisor declined to comment about specifics about Mr Butler’s listing and claims, but said that it was already the subject of a review before his article came out.

“In fact, we had already applied a penalty to the property which reduced its position within our Popularity Ranking and removed a number of its reviews,” a statement distributed by spokesperson Brian Hoyt said.

The hoax hints at deeper vulnerabilities with the process the company uses to verify the content on its site, which is driven in part by algorithms and automated monitoring. And it brings to mind other online platforms, such as Facebook and Twitter, whose algorithms have been goosed by dishonest actors to much graver consequences.

Last year, a gunman entered a Washington pizzeria after false rumours that it was the home to a politically connected paedophilia ring proliferated on Twitter and other forums; the rumour appeared to have been amplified on the service by bots in places including the Czech Republic, Cyprus and Vietnam.

Some people reading the story were quick to see The Shed’s story as an allegory. A cartoonist in London for the Evening Standard newspaper drew a parallel to Brexit, where, like in the United States, misinformation spread by Russian trolls online is believed to have had at least a small effect.

Dan Biddle, a former Twitter employee, called Mr Butler and his experiment the “Donald Trump of TripAdvisor”.

TripAdvisor was recently the subject of sharp criticism after an investigation by the Milwaukee Journal Sentinel found it had been deleting reviews that described dangerous activity, like theft and rape, from some listings.

A promotional video made by the company said that every review went through electronic checks.

“We know that in order for a review to be truly useful, it has to be true,” the video stated.

Mr Hoyt said the company’s process was more tuned to catching fake reviews, not fake reviews for fake businesses.

“Most fraudsters are only interested in trying to manipulate the rankings of real businesses, so naturally that is what our content specialists are focused on catching,” he wrote.

“Generally, the only people who create fake restaurant listings are journalists in misguided attempts to test us. As there is no incentive for anyone in the real world to create a fake restaurant it is not a problem we experience with our regular community — therefore this ‘test’ is not a real world example.”

Mr Butler said they decided to open the fake restaurant for one night, populating the tables with a mixture of actors having the time of their lives — “to re-create the same psychological space as TripAdvisor” — and foodies who had seen the listing.

Mr Butler and a friend prepared an inexpensive meal made from instant food. He said in his story and interviews that at least one patron — a non-actor — had asked whether he could book the restaurant again.

The Washington Post/WP Bloomberg