A copy of Action Comics #1 - featuring Superman's first appearance - that was found behind the wall of an abandoned home is being auctioned by Comic Connect.
The heralded comic is currently selling for $113,111, having received 32 bids from eager collectors.
It's not often that a sound example comes up for auction and the sale still has 19 days before it closes on June 11.
The rare first issue is one of the most celebrated comics ever published, ushering in the age of super heroes with its introduction of Superman - the archetype for all characters to come.
It is also the world's most valuable comic, with a 9.0-graded copy formerly owned by Nicholas Cage selling at Comic Connect for $2.1m in 2011.
The present copy was discovered by a contractor named Gonzales, who discovered the comic behind the wall of a 1930s home in the US that he was in the process of renovating.
The 1938 publication had been used as insulation in the walls of the house, which were also filled with period newspapers.
Despite its long service as insulation, the issue is in surprisingly good condition and has been graded CGC Fair/Good 1.5.
It won't sell for as much as the 9.0-graded example, but has already surpassed the $77,333 seen by a restored 2.0-graded copy in January.
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