History is made, with a new member joining! Oh, and awesome, iconic cover by Carmine Infantino and Murphy Anderson.
The Story: "In Each Man There Is A Demon!" by Denny O'Neil, Dick Dillin, and Joe Giella. Green Arrow opens the story as narrator, telling us that he recently has been framed by a business named, and in doing so losing his vast fortune!
Meanwhile, back at the Secret Sanctuary, the JLA is debating whether to admit Black Canary into the team. Canary grows frustrated at the all-male team's patronizing attitude towards her, and suddenly lets loose with a sonic scream, a power she never possessed before!
We return to Oliver Queen, who is subjecting himself to experiments with a Dr.Oyal, which allows a subject to peer into their subconcious! A malevolent Green Arrow springs from Ollie, knocking Oyal out and heading for JLA HQ!
When the JLAers(who figure that exposure to Aquarius' radiation caused Canary's new power) get attacked by the evil GA, evil duplicates are created of them, as well, all from the mystic residue left in each of them by Aquarius! Only Superman remains unaffected, because, as he assumes, he didn't absorb any of Aquarius' radiation. The JLAers feel despondent, not believing they can defeat themselves.
Superman gives them a super pep-talk by fighting a Superman robot, and defeating it, telling them it was an evil inner duplicate of him, too. This inspires them and they head off to fight their duplicates.
Green Arrow faces down his inner bad self by admitting that evil resides in all people, and it is the best part of them that keeps the evil side under control. This drains the evil dupes' energy, and they return to their hosts.
Roll Call: Superman, Batman, Green Arrow, Atom, Hawkman, and new member Black Canary!
Notable Moments: There's no official approval of Black Canary into the team--by the end of the story, she's simply a member, recording the tale into the JLA archives with Green Arrow.
The letters page only runs three letters, one by Alan Brennert and one by Martin Pasko--a pretty damn good eventual-writers-to-fan ratio.
While the addition of Black Canary makes total sense, dramatically and otherwise, I do feel like it was a small step down, Iconic Hero-wise. Black Canary never had her own book, only her own strip in Flash Comics, and even that had ended over fifteen years earlier.
Starting with Canary, the JLA would accept heroes whose only home was the JLA, and one could make the argument it weakened the initial Knights of the Round Table concept that the team started out with.