The sorceress Morgaine Le Fey and her son Mordred search for the Philosopher's Stone, and the Justice League need the help of the Demon Etrigan to thwart her.

Morgaine and Mordred get the Stone and plan to transform England and restore it to its medieval glory.

The Justice League is forced to ally with Darkseid against an enemy powerful enough to threaten both Earth and Apokolips.

The League are forced to battle both Darkseid and Brainiac, while Wonder Woman and Batman seek the aid of Orion, son of Darkseid.