For 15 years, Sara Michaelson was clueless to what her husband kept tucked away in a cardboard box.

Mark Michaelson never meant to keep it a secret — he’d had the rare, Superman #1 comic book since scoring it for a few thousand dollars from a Houston oil executive in 1979. It was “a coup,” Michaelson would later joke, that came with one simple, but heartfelt, request from the book’s then-owner: “Cherish it for forty years, like I did.”

And so he did, and told no one - until last month, when he surprised his wife, a fellow collector whom he met through a shared love of comics, with the protective-encased first edition of DC Comics’ Superman. She stared in shock as she sat at the dining room table of their north Houston home.

“I’m not touching that,” she half-joked as she cautiously edged away from the table. “Put it back.”

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She had good reason to keep it pristine: On Thursday, it sold for $2.6 million at an auction, the final sale price jumping by $400,000 in the final hour of bidding.

It’s a record for Superman #1, and the latest seven-figure sale in an industry that’s boomed as investors have swarmed in, looking for new assets that might yield big returns.

“I am just very fortunate,” Mark Michaelson said Friday as he and his family headed to a Japanese barbecue spot for a celebratory lunch.

Rare form

Sold for a dime in 1939 by the company that became DC Comics, Superman #1 is not the first time that the Man of Steel appeared on pulp. That came a year prior, in Action Comics #1, a copy of which recently sold for $3.25 million.

The full-color, 64-page book, however, is the first full-spread introduction of Superman and, with it, a genre that would redefine the entertainment industry. Only about 150 are known to still exist, and most are all-but destroyed or have been refurbished.

“Most of the copies that I have seen are literally disintegrating,” said Stephen Fisler, an expert on comic book sales and head of the auction website ComicConnect. “Unless you basically don’t touch it at all, it starts to disintegrate.”

Michaelson’s copy was particularly well-preserved, scoring a 7 on the 1-10 scale used by the industry to grade conditions. Fisler immediately knew the comic could fetch north of $2 million at auction, and was encouraged to see bidding reach $1.8 million within days of opening.

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Such prices would have been unthinkable even a few years ago, before the comic book trade became a magnet for well-to-do investors fleeing traditional markets after years of crashes and volatility. But now, as anonymous investors continue to pump cash and competition into the market, six- and seven-figure sales are almost unremarkable.

“People throw around million-dollar figures for comic books seemingly at will these days,” said Fisler, who helped auction the first $1 million comic in 2009. “Now, people have sort of gotten used to it.”

Even before the Superman sale, the industry had been lucrative for Mark Michaelson. He was paying his way through University of Houston in the 1970s when, after unexpectedly netting $300 in sales at a local comic book event, he realized there was money to be made in the flourishing, but still relatively new, trade.

He went on to work as a health care executive, collecting comics as a fun and lucrative side hustle that’d later pay for his college and a house. Today, the semi-retired 67-year-old often serves as a liaison between sellers and collectors. He is used to handling comic stacks that can cost more than most cars.

That much was clear on a recent Monday, as he sat near his antique radio collection and sifted through a pile of early-edition Marvel comics that a client had requested that morning.

A quick Google search priced just one of the books at between $100,000 and $300,000.

New buyers

So, what’s driving prices that high?

Michaelson said its nostalgia and pure, simple fandom that prompts clients to shell out small fortunes for cartoons. But it’s not just about the book. Like so many others, Michaelson met many of his closest friends through the tight-knit, welcoming comic community, which only adds to the sentimentality of collecting.

Others agreed that nostalgia was a huge driving force. “Simply put, the value of anything is what someone is willing to pay for it,” said Jerry Hionis, a professor of economics at Widener University in Wallingford, Penn.

But Hionis also pointed to another potential driver of comic book prices: The growing interest from investors seeking alternatives to stocks and bonds after years of unpredictability, low interest rates and now, high inflation.

The comic book industry saw a similar influx of interest decades ago, after the baseball card market stumbled, said Hionis. With that came a wave of collectors who reinvested in comics “not because they wanted them, but because they saw it as an investment to sell to someone else.”

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The result? “You had the value of all these comics rocketing, and then people realized no one really wants them, and their value crashed down,” he said.

Decades later, their value has rebounded, thanks in part to blockbuster film franchises that have helped sustain interest in superheroes. The pandemic was also a boon for the comic book industry, with sales skyrocketing as people spent months at home, indoors.

Michaelson is just happy to have passed along his Superman #1. He’s unsure of the identity of the anonymous, top bidder and, now, third owner of the prized book. He may never — and that’s fine, he said.

He’s just happy to have lived up to the promise he made four decades ago.

“I was very lucky to have it,” he said on Friday morning. “But now, my 40 years is up. I just hope somebody else enjoys it.”