An original first edition copy of Superman No. 1 from 1939 has sold at auction for a record-breaking $9.12 million, making it the most expensive comic book ever sold.The comic was discovered last year in an attic in northern California by three brothers who were sorting through their late mother’s belongings, and the sale surpasses the previous record of $6 million set by Action Comics No. 1.Heritage Auctions’ vice president Lon Allen praised the comic’s rare condition and remarkable discovery story, and Superman was created by Jerry Siegel and Joe Shuster in 1933.