Episode 1
After unsuccessfully attempting to recruit the Green Arrow to join the expanded League, he plays an important role with a team sent to manage a crisis in Asia.
Episode 2
Batman and Wonder Woman find Superman immobilized in the Fortress of Solitude by a plant sent by the would-be conqueror Mongul.
Episode 3
Morgaine Le Fey transforms Superman, Batman, Wonder Woman, and Green Lantern into children after Mordred uses his magic to remove all adults from Earth and keep children on the Earth.
Episode 4
Ares creates a war machine called the Annihilator to escalate a civil war in Kasnia. Hawk, Dove, and Wonder Woman try to stop his plans.
Episode 5
When Circe changes Wonder Woman into a pig, Batman and Zatanna must find her and change her back.
Episode 6
Supergirl, Green Arrow, and The Question investigate Supergirl's disturbing dreams. They discover that Cadmus created a clone of Supergirl named Galatea while she was recovering from her fight against Superman on Earth.
Episode 7
The Justice League battle Mordru in the background, while the narrative follows Booster Gold as he attempts to close a walking black hole while he's supposed to be on "crowd control".
Episode 8
After blasting through the entire Green Lantern Corps, the android Amazo returns to Earth. Only the Justice League stands between him and his goal -- the now-reformed Lex Luthor.
Episode 9
A team of too-good-to-be-true superheroes find out the truth about their origins and go on the rampage.
Episode 10
Most of the League battles with powerful alien nanotechnology but, realize that the waves of self-replicating robots cannot be simply destroyed. The diminutive Atom shrinks himself to stop the robots from the inside.
Episode 11
A trio of high school kids accidentally resurrect Solomon Grundy, reviving him more powerful than ever but with no memories of his past. Dr. Fate, Amazo, Aquaman, and Shayera assist League regulars stopping his rampage.
Episode 12
While pursuing a time traveling thief, Batman, Wonder Woman and Green Lantern team up with a collection of DC Universe western heroes to battle the villain controlling him.
Episode 13
The time traveling League team goes to the future to team up with that time's League to battle Chronos who rules.