As Green Lantern is protesting his superiors' decision to keep him on Earth, the entire planet of Oa disappears. The culprit is Amazo, Dr. Ivo's android from [[Recap/JusticeLeagueS2E3And4TabulaRasa "Tabula Rasa,"]] and he's come back for Luthor. Every member of the Justice League mobilizes to stop the android, who tears through the League's three layers of defenses with ease. Luther hides in a specially constructed panic room, and he and [[ComicBook the Atom]] start to build a last-ditch weapon to destroy Amazo. Meanwhile, an angry Green Lantern Corps shows up to take vengeance for Oa -- they want to blast Amazo with everything they've got in their rings in an explosion that could destroy half the world. [[ComicBook/DoctorFate Dr. Fate]] protests this and teleports out, resolving to find another way.
Soon, the android has blasted through every defense. Not even the nano-disassembler beam that the Atom and Luthor built stops him. The Atom shrinks both of them down to evade capture, but they find themselves in Amazo's hand. The android doesn't kill them, but instead reveals the reason he came: having learned and grown into an extremely powerful being, he doesn't know what to do with all that power. Luthor explains that he'll be able to see the whole universe, and that the android needs to make his own fate.
Dr. Fate and The Green Lanterns show up in the bunker. The Corps are ready to fire their rings...and then Amazo explains that he didn't destroy Oa; he just moved it to another dimension. He puts it back with only a thought. Dr. Fate offers Amazo help in finding his purpose, an offer the android accepts. The two of them go to Fate's house, which Fate and his wife are sharing with another hero: Shayera Hol.
* BadassBoast: As the assembled Lanterns demand Doctor Fate get out of their way:
-->'''John''': Not even you can stand against the Green Lantern Corps.
* BreakThemByTalking: Luthor talks down the android to prevent him from [[SuicidalCosmicTemperTantrum destroying the world out of anger.]]
* CurbStompBattle: The entire League ends up facing AMAZO, and they can barely even delay him.
-->'''AMAZO''': ''[facing heroes for the third time]'' When will you learn?
** Luthor's panic room is underneath a barbershop. Steel breaks this out.
---> '''Steel:''' Gotta hand it to you, Luthor. Nobody would [[BaldOfEvil think to look]] for you here.
*** He then asks what's next after Luthor gets his nose hairs trimmed.
** The Atom in spades since he's voiced by John C. [=McGinley=].
* DoubleMeaningTitle: TheBusCameBack for both AMAZO and Shayera.
* DroppedABridgeOnHim: Amazo did this to the ''entire planet of Oa''. But, he eventually reveals that he just moved it to another dimension, and puts it back with only a thought.
-->'''AMAZO''': It was in my way.
* GrewBeyondTheirProgramming: In a few months, AMAZO has evolved from a nanotech android into a PhysicalGod.
* HalfTheManHeUsedToBe: Amazo tears [[ComicBook/RedTornado Red Tornado]] clean in half. Fortunately, this version of Red Tornado is an android himself, and he eventually gets better.
* LivingForeverIsAwesome: Luthor's view of it. He notes that he'll eventually die and that his name will be forgotten after a few generations, while AMAZO will just keep going and going.
* NoSell: The android tears through everything the Justice League and Luthor can throw at him without so much as slowing down. The Atom and Luthor build a nano-disassembler machine, and even that doesn't work.
* PetTheDog: Doctor Fate offers to help AMAZO find his purpose.
* RoaringRampageOfRevenge: What the League assumes AMAZO wants, since Luthor took advantage of the android. [[DesperatelySeekingAPurposeInLife However, the android's looking for something else altogether,]] and he came back because he thought Luthor had the answer.
* WhamShot: The final scene shows that Shayera has been staying at Doctor Fate's tower.
* WhoWantsToLiveForever: Part of AMAZO's problem is that he's effectively immortal but with no defined purpose.
* WorldWreckingWave: This appears to happen to Oa. In revenge, the Lanterns plan to throw every last bit of energy in their rings at AMAZO, which could destroy half of Earth.
--> '''Kyle Rayner:''' Half a planet's better than none.
* TheWorfBarrage: ''Hundreds'' of superheroes with all sorts of different powers, including multiple Green Lanterns, heavily armed robots, ''two'' Kryptonians, and more, all try and stop Amazo and lose ''badly.''