Zatanna contacts the Atom for help when she seems to be losing her magical powers (a gradual development from previous issues), but the affliction appears to be widespread, as other JLA members on individual cases also find themselves bereft of their super-abilities, including the Flash, Black Canary, Elongated Man and the Atom himself. The culprit is the android Amazo, reactivated against his will by the Key, who is stealing the League members’ energies for his own use and to cure the Key of his dwarf state (suffered as a side effect of his previous cure in issue #150). With Hawkman’s aid, the superheroes track down and defeat Amazo, while Zatanna magically cures the Key of his affliction. In the aftermath of the battle, the Atom learns that Zatanna’s power loss is a separate phenomenon, caused by her overuse of her skills in previous cases, and that her powers are permanently reduced as a result.
The Key recovers the inert body of Amazo. Upon reactivation, Amazo attacks the Key, and must be forcibly subdued. Zatanna meets with physicist, Ray Palmer, in Central Park. Zatanna confesses that she is losing her sorcerous powers. The Flash foils a train robbery, then brings the runaway train to a stop. As the Flash races off, he suffers a sudden muscle cramp in his right leg, heralding the loss of his ability to move at super-human speed.
The Black Canary chases after a band of modern day pirates. After disabling their vessel, the Black Canary takes on the crew. In mid-Canary Cry, her sonic scream chokes off, forcing her to rely on her martial arts mastery. Ralph Dibny, and his wife, Sue, are vacationing in the Rocky Mountains. Stretching his arm across the room, Dibny's elongated reach falls short of his grasp. Suddenly, Dibny's arm snaps back, losing it's elasticity altogether.
Dibny consumes another dose of Gingold, hoping it will restore his powers. When it doesn't, Dibny makes his way to the satellite headquarters of the Justice League of America, as the Elongated Man. The Elongated Man finds the Atom, the Black Canary, the Flash, and Zatanna suffering from the same power loss.The Flash is hurt that Zatanna would go to Palmer for help, instead of coming to him. The Hawkman determines that each of the heroes powers have, essentially, reached the end of their natural lifespan.
The Hawkman also determines that it is Amazo who has caused this dilemma. The Key absorbs the life energies of the afflicted members of the Justice League of America, through Amazo. The combined life energies restore the Key to normal, reversing his hideous deformation into a shriveled dwarf, the result of a previous scheme gone awry. The Justice League of America confront the Key. Amazo attacks the Justice League of America.
The Justice League of America fight a losing battle with Amazo, drawing it out as long as possible, to re-absorb their stolen life energies from Amazo. With the Justice League of America defeated, Amazo turns on the Key. Their powers restored, the Justice League of America destroy Amazo. Zatanna uses a percentage of her life energy to permanently restore the Key to normal. The permanent loss of a percentage of her life force diminishes Zatanna's sorcerous powers. Zatanna is left only with the power to command natural forces, and can no longer conjure elements out of nothingness.
Note: This issue contains the Hostess Superhero Ad, Hawkman in "She's no Angel".