Rare Superman comic breaks record and becomes most expensive ever sold at auction

A rare first edition of Superman, discovered by three brothers in their late mother's attic, has fetched a record-shattering $9.12m (€7.9m) at auction in Texas, US, making it the most expensive comic book ever sold.

“Superman No. 1” breaks the record previously held by “Action Comics #1”, which sold last year for $6m (€5.5m) and which also featured Superman on its cover, as the influential comic introduced the character to the world.

The brothers discovered the comic book in a cardboard box beneath layers of newspapers and cobwebs in their deceased mother's San Francisco home last year, alongside a handful of other rare comics that she and her sibling had collected on the cusp of World War II.

She had told her children she had a valuable comic book collection stashed away, but they had never seen it until they put her house up for sale.

Lon Allen, vice president of comics at Heritage Auctions, was contacted by the brothers and travelled to San Francisco to inspect their copy of “Superman No. 1”.

“It was just in an attic, sitting in a box, could have easily been thrown away, could’ve easily been destroyed in a thousand different ways,” Allen said. “A lot of people got excited because it’s just every factor in collecting that you could possibly want all rolled into one.”

The "Superman No. 1" comic, released in 1939 by Detective Comics Inc., is one of a small number of copies known to be in existence.

A small, in-house advertisement within the comic helped experts identify it as originating from the first edition of 500,000 "Superman No. 1" copies ever printed. Allen estimates there are fewer than 500 in existence today.

Despite lacking any special protection, the cool Northern Californian climate helped preserve it, leaving it with a firm spine, vibrant colours, and crisp corners, according to a statement from Dallas-based Heritage Auctions.

The copy was rated a 9.0 out of 10 by comics grading company CGC, meaning it had only the slightest signs of wear and ageing.

The three brothers, aged in their 50s and 60s, did not wish to be identified, nor did the buyer of the comic book.

"This isn’t simply a story about old paper and ink," one brother said in a statement released by the auction house. "This was never just about a collectable. This is a testament to memory, family and the unexpected ways the past finds its way back to us."