The 853rd century: one million months after the publication of Action Comics #1 and the introduction of Superman. Humanity has expanded to colonize the solar system, and the JLA's successors, Justice Legion Alpha, defend a planet each. Superman is still alive, but lives in self-exile at the heart of the sun. When Superman announces his return to humanity, Justice Legion A travel to the 20th century to meet their fore-bearers. This encounter nearly becomes their doom, however, thanks to the evil machinations of the immortal Vandal Savage and the sentient super-computer Solaris, the Tyrant Sun.