The ultimate conquering force has been released into the universe, and it's heading towards Earth, leaving a path of galactic devastation in it's wake. The DC Universe will be shaken to it's core, with one hero-Superman-pushed to his limit as Earth becomes embroiled in a galactic war against a seemingly unstoppable enemy.
Volume One finds Superman forging uncertain alliances with President Lex Luthor, Darkseid and other dubious allies to help the DC Universe heros battle the force known as Imperiex.
Volume Two shows the war going badly for Superman and his allies. With several of DC's greatest heroes having fallen or gone missing in battle, Branicac secretly enters the war seeking to harness the power of Imperiex for his own ends.