Challengers of the Unknown #81, a vintage comic book from DC Comics, features a striking cover by Neal Adams and Michael Netzer. The comic is graded 7.5 Very Fine- and is a first printing from 1977. The comic book follows the adventures of the superhero team, the Challengers of the Unknown, as they face off against various villains in the DC Universe. The issue features characters such as Rocky Davis and Professor Haley and is a great addition to any comic book collection.