Claudette, Cooch's former owner, returns with a lawyer seeking to get her cat back, so Robobot agrees to represent Rex in the upcoming trial; the Groaner tries to discern the true meaning behind Black Saturn's name.

When Cooch's claims that Leprechauns are attacking Storm City turn out to be true, the League of Freedom is drawn into a battle with assorted mythical creatures. The injured Black Saturn recruits Courtney to join the fight in a mechanized suit.