In the spring of last year, one of Seattle’s many bike thieves arrived at a meeting place, expecting a payout.

A few days earlier, the thief had listed the bike for sale on Craigslist. A local man had said he was interested. Now the two strangers were meeting face-to-face, supposedly to make the exchange.

The potential buyer was an imposing figure. He was 6-foot-4 and had pale skin with a widow’s peak of dark blond hair.

He also had full knowledge that the bike was stolen.

Instead of money, he gave the thief a choice.

“You’ve got two options. You can wait until a cop gets here,” he told the thief, according to the Guardian. “Or you can just beat it.”

Just like that, Bike Batman was born.

For the past year, Bike Batman has waged a one-man battle against bike theft in Seattle. The unidentified cyclist has become a hero by returning 22 bicycles to their rightful owners, according to the Guardian. In at least a dozen cases, cops also have arrested the alleged culprit.

“The bike would never have been found if it weren’t for him,” said Douglas Brick, 65, whose expensive road bike was snatched last summer, in an interview with the Seattle Times.

But like his namesake, Bike Batman’s crusade has not come without cost. There have been tense encounters with bike thieves, who comprise their own sprawling League of Shadows. And then there is Bike Batman’s secrecy, which he closely guards.

Like his namesake, Bike Batman lives a double life. By day, he is a married engineer in his 30s, according to the Guardian. In his free time, however, he is precisely what this city of fixies and fast-fingered thieves so desperately needs.

A vigilante.

The remarkable story of the real-life superhero was revealed Monday morning, when Seattle Times reporter Evan Bush exposed the Bike Batman’s existence, if not his identity. (Both the Times and the Guardian agreed to withhold the Bike Batman’s name.)

Bush reported how several Seattle residents had their bikes stolen, only to be approached by a stranger who said he could get them back — no strings attached.

Sierra Bronson’s Specialized Dolce was snatched out of her garage. She called the cops, made a report and posted the purloined bike’s details online.

Bizarrely, a man then got in touch with her saying he had spotted online what he suspected was Bronson’s bike. He even offered to get it back for her.

“I figured I didn’t have anything to lose,” she told the Seattle Times.

“He gave the guy the ultimatum: Either you can give me the bike now or you can wait until the police show up and then we can figure it out,” Bronson said.

The man handed over the bike, and a grateful Bronson handed over some beers to her mysterious savior.

“The impression I got from him, and stuff his wife said, [is] he’s kind of an adrenaline junkie,” she told the Times. “It’s his way of giving back to the community.”

Bronson dubbed him “the bike repo man,” but the good Samaritan would come up with a better nickname.

A police officer impressed by his antics suggested “Robin Hood,” but Bike Batman felt that the dark knight’s dealings with the criminal underworld were a closer match.

“It’s kind of fun,” he told the Guardian, adding that although he finds the superhero label silly, it felt good to catch thieves and uphold the city’s friendly reputation.

Not even Bike Batman operates all by himself, however. He has help from a website called Bike Index, which people across the country use to report stolen bicycles. Bike Batman compares descriptions of those stolen bikes to photos listed on Craigslist and other Internet marketplaces. He then confronts the seller with proof the bike was stolen and calls — or threatens to call — the cops.

Few cities are as desperately in need of Bike Batman’s services as Seattle, a city of 650,000 people with a cycling culture.

The city also has an ongoing heroin epidemic, however, which fuels petty crime, including boosting bikes.

“It’s a small community of criminals, but they’re all intertwined, chasing the same heroin and meth,” Seattle Police Detective Scotty Bach told the Times.

In 2015, 1,561 bikes were reported stolen in Seattle, according to the Times. The real number is likely much higher.

Many of those hot bikes end up on Craigslist, Seattle Met reported. But when bike activists like Bryan Hance, co-founder of the Bike Index, complained, they got the cold shoulder.

“The minute you start pointing out that they’ve got stolen goods, you’ve violated their terms of service and they’ll send you a cease and desist,” Hance told SeattleMet.

Hence the need for a superhero like Bike Batman.

The vigilante has come a long way since a year ago, when he was terrified by his first confrontation with a bike thief.

“My heart was pounding,” Bike Batman told the Guardian’s Sam Levin in what appears to be the superhero’s first interview. “I had no idea what I was doing.”

He now works closely with cops to catch the thieves. And he felt comfortable enough to provide the Guardian with a photo of himself, albeit wearing sunglasses.

“He’s done some amazing things,” said Hance, who is a bit like Bike Batman’s Alfred. Although other activists help track down stolen bikes, Hance said Bike Batman is the only one he knew of who personally confronts the culprits.

Bike Batman is humble about his achievements, however.

“I’m not out fighting crime and punching people,” he told the Guardian. “I’m telling people: This is not yours.”

Whether it’s crime-fighting or Craigslist-surfing, the Bike Batman’s work is clearly appreciated.

“It was so cool. My heart was just beating so happily,” Brick said of the moment the Batman returned his Volagi Viaje, worth several thousand dollars. “This guy is the real deal.”

Read more about Seattle: