"Princes of Darkness" builds to a fever pitch with Part 4 of 5! The JSA call in the reserves to help take on the dark forces that are plaguing the world, from Obsidian's shadow-army to the fanatics of Kobra. Meanwhile, Dove, Power Girl and Hawkgirl venture out in search of the one lost soul who can stop Mordru, while Wildcat and Hourman make a daring attack on Eclipso!