A first issue of Action Comics—which introduced audiences to Superman in 1938—has become the world’s most valuable comic book, selling at Heritage Auctions in April for $6 million. The ...

(CNN) - A vintage high-grade copy of a forgotten Superman comic book set a record at auction on Thursday. Superman No. 1 from 1939 was sold for a little over $9 million by Heritage Auctions.

The comic book was found by three brothers while they sorting through the things in their late mother’s attic. Buried below piles of old newspapers, it was one of six comic books their mom had ...