First published in 1948 by the American Comics Group, Adventures Into The Unknown was the first regularly published horror comic book and it’s success led several other comic book companies, most notably EC Comics, to start publishing horror comics of their own.  Because Adventures Into The Unknown‘s content was never as explicit as some of the comics that it inspired, Adventures became one of the few horror comics to survive the anti-comic book moral panic that erupted in 1954.  Unlike Tales From The Crypt and The Vault of Horror, Adventures Into The Unknown continued to be published after the creation of the Comic Book Code.  In total, it enjoyed a 20-year run of 174 issues.

Below are some of the many covers of Adventures Into The Unknown.  As you can tell, the covers went from emphasizing horror to emphasizing science fiction and adventure after the creation of the Comic Book Code.