A green slime coming out of Lake Erie threatens to overrun Detroit. Aquaman visits an old friend, Don Powers, owner of Powers Investigations, an investigation firm helping Detroit police fight crime. Powers' firm is also responsible for a satellite meant to stop crime but is also the cause of the slime. Powers is the Crusader, though losing his eyesight, he wants to continue fighting crime using the satellite. On a last patrol, Crusader dies from a fall from a building due to his deteriorating eyesight. Aquaman discovers his death, then breaks into Powers' business and destroys the satellite; Aquagirl saves a boy falling into the Cave of Death.