As several JLAers experience a sudden power loss, Flash finds that someone has used powers like theirs to steal a European catfish and a cicada. Snapper suggests the thefts have to do with someone researching immortality, and the JLA splits up to investigate other long-lived creatures. In every case, the JLAers come up against Amazo, who steals their powers, defeats them, and takes them to his creator's lab, where Professor Ivo is preparing an immortality serum. Green Lantern is able to use the weakness of his own ring against Amazo and Ivo, restore the JLA's powers, and defeat the villain.