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.

The team heads to Hawaii where Titanium Rex (Bryan Cranston) runs into a vacationing former President Barack Obama (Jay Pharoah), Black Saturn (Tucker Gilmore) and Lex (Jillian Bell) teach Cooch (Heidi Gardner) how to swim, and American Ranger (Keegan-Michael Key) attempts to perform in a USO show while an evil threat brews under the sea.