After the events of Justice League: War, Ocean Master and Black Manta have declared a war against the surface in retaliation of the aftermath of Apokoliptian-tyrant Darkseid's planetary invasion. Queen Atlanna seeks out her other son, Ocean Master’s half-brother Arthur Curry, a half-human with aquatic powers with no knowledge of his Atlantean heritage, to restore balance. Living with powers he doesn’t understand and seeing the danger around him, Curry takes steps to embrace his destiny, joining the Justice League, and with his new teammates he battles to save Earth from total destruction.

Based on the Geoff Johns/Gary Frank 2008 release "Superman: Brainiac," Superman: Unbound finds the horrific force responsible for the destruction of Krypton (Brainiac) descending upon Earth. Brainiac has crossed the universe, collecting cities from interesting planets, Kandor included, and now the all-knowing, ever-evolving android has his sights fixed on Metropolis. Superman must summon all of his physical and intellectual resources to protect his city, the love of his life, and his newly-arrived cousin, Supergirl.