Superman's action comics number one. Has set a record with a sale of $6 million. Hear about it at urban legends and stranger truths. A rare copy, just one of about 100 in existence. Has topped Superman as being number one. As the most valuable comic in the world. Superman left that world record in a single bound. An issue of action comic number one, which introduced the world to the kryptonian hero Superman. Sold at auction for a record $6 million