Inside Cadmus, Captain Atom takes on Superman. In addition to his super-strength, Captain Atom can produce red sun energy blasts that weaken Superman. As they fight, Huntress takes Question out of the building and calls the Watchtower for an emergency teleport.

Captain Atom gives it everything he's got, but is no match for Superman's strength. Superman is forced to give him a severe beating, coming dangerously close to cracking his containment suit, before Captain Atom finally stays down. When Cadmus doctors arrive to see to Captain Atom, Superman tells them to back off. No one tries to interfere as Superman carries him out and back to the Watchtower.

Superman visits Question in the infirmary, who confesses that he was afraid Superman was coming close to killing Luthor. Superman insists that that would be impossible, but Question reminds him that Cadmus have been remarkably effective in bringing out his worst side.

Superman tells Supergirl the truth about Emil Hamilton, and together they storm up to the bridge, ready to assemble a team to go down and smash Cadmus before they make another move against the League, despite expecting to be refused. As he expected, J'onn J'onzz and Green Arrow remind them exactly why they can't, because they are committed to upholding the law, and Cadmus may actually be a legitimate, albeit secret, branch of the government, which on its own commits crimes. Furthermore, such action is precisely why ordinary humans fear the League. Flash further cautioning Superman and Supergirl against acting out of revenge, citing 'An eye for an eye leaves everyone blind'.

Working in his laboratory at [=LexCorp=], Lex Luthor receives a call from Amanda Waller about the break-out. She warns him that if Question has gotten evidence to implicate Luthor, Cadmus will cut him loose. Seeming unconcerned, Luthor strides to a targeting computer in his lab that has just beeped ready, and presses "Enter".

The debate aboard the Watchtower is interrupted when the computer announces that the binary fusion cannon is preparing to fire. J'onn tries to override the system, but he is locked out. As a last resort, he tears the circuitry out of the control panel, but the system re-routes. Superman hurtles out of the station and to the mouth of the cannon, but is a split second too late: the laser fires down at the Earth's surface.

Down below, people are going about their daily lives, but pause when they see the sky light up: the beam lances down and hits an abandoned building marked "Condemned". The building is vaporized, and a massive shock wave ripples out, hitting the surrounding city with the force of an earthquake.

Aboard the Watchtower, the discharge has drained the station's power for a whole hour. Even without sensors or communications, J'onn can tell that the League has fired on Cadmus's headquarters. Flash leads a rescue team down to the surface to help those caught in the shock wave.

J'onn receives an angry call from the President of the United States on a special hotline, but swears that the League was not responsible for the blast. Afterwards, the President receives a call from Waller revealing that the facility that was destroyed was empty. They evacuated an hour earlier because of the break-in by Superman.

Waller advises the President in the strongest terms to order retaliation: the blast (in her eyes) was clearly retribution for kidnapping Question, and the League and the government are officially at war. The President is reluctant to order retaliation, and tells Waller to stand by.

The League is at its best on the ground, rescuing people trapped by the devastation. But things turn ugly as rumors start to fly that the League fired the cannon at Earth.

At Cadmus's new facility, Waller grows impatient and decides it's time to act. She orders a fully operational Galatea to take command of an army of Ultimen clones.
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!!Tropes:
* BaitAndSwitch: After the Binary Fusion Generator fires, there are a series of shots to a city of innocent bystanders before the sky lights up ominously... only for the blast to ultimately strike an empty building. Slightly averted in that those people are caught in the blast radius, albeit non-lethally.
* BewareTheSuperman:
** Invoked by Huntress on Captain Atom, who really should’ve listened.
-->'''Huntress:''' Dude, ''Superman'' just told you to step aside.
** Discussed by Arrow.
-->'''Green Arrow:''' Hey, I'm the only guy in the room who doesn't have superpowers and let me tell you, you guys scare me. What if you do decide to go marching down there, taking care of whoever you think is guilty? Who could stop you? Me?
* BothSidesHaveAPoint: Superman is right that Cadmus is engaged in some very corrupt activities and has been belligerent towards the League. On the other hand, Green Arrow and J'onn point out they can't just take the law into their own hands here and that Cadmus might be a necessary counter-balance to the League.
* {{Cliffhanger}}: "Get it done."
* DoubleMeaning: Luthor ends his phone conversation with Waller by saying "Good-bye, Mrs. Waller", followed by activating his targeting computer that hacked the Watchtower's cannon to fire at Cadmus headquarters, giving his parting words with Waller a DeadlyEuphemism.
* FromBadToWorse: The war between the League and Cadmus spirals out of control, thanks to Luthor's sabotage of the League's cannon. The League is finding little popular support among the citizenry, and Waller is going to unleash a metahuman army at the League's Watchtower.
* GetOutOfJailFreeCard: Deconstructed when Waller warns Luthor that with Question having been rescued by Superman, the League might now have the evidence connecting him to Cadmus. Luthor is dismissive, arguing he's got a full pardon from the President. Waller points out the pardon was ''only'' for his crimes committed prior to Season Two's "A Better World"; it ''doesn't'' cover any subsequent crimes, like his illegal activities with Cadmus. If he gets caught this time, Cadmus will disavow any knowledge of Luthor. Of course, Waller doesn't realize that Lex being dismissive isn't arrogance, but rather because he knows the League's about to have bigger problems thanks to the FalseFlagOperation he's seconds away from triggering.
* HopeSpot: Unable to deactivate it through normal means, J'onn literally rips out the wires to stop the cannon from firing. Then the command bypasses this circuit break. Also, Superman flies out into space to try to damage the blaster, but just as he gets there, it fires.
* ItsAllMyFault: Green Arrow doesn't care if someone overrode the cannon's controls. It was the League's weapon and therefore their responsibility.
-->'''Green Arrow:''' [[NoManShouldHaveThisPower It's too much power for anyone to have]].
* ItsPersonal: Supergirl when she learns that Hamilton is working for Cadmus and stole her DNA to create Galatea.
* MoralityChain: While trying to talk sense into Superman, Green Arrow points out this is why Batman wanted him on the team.
--> '''Green Arrow:''' Batman said I was supposed to keep you guys honest!
* MythologyGag: Superman shouting at a government agent not to touch a downed Captain Atom evokes a similar moment following his famous battle with Batman in ComicBook/TheDarkKnightReturns.
* OhCrap: The reactions of Clark, J'onn, and the other Leaguers when the BFG activates and their attempts to override and shut it down fail.
* ProperlyParanoid: The President has apparently voiced his disapproval of the Justice League having a KillSat.
* ReportsOfMyDeathWereGreatlyExaggerated: The President is surprised when Waller calls, being under the assumption that she and the rest of Cadmus was killed by the Watchtower's cannon.
* ScrewTheRulesImDoingWhatsRight: In an ironic example, Waller of all people does this in response to the President delaying an immediate retaliatory strike against the League. From her perspective, it ''is'' justified: The League launched an attack on a Federal facility and would've killed them all. The President is indecisive, all their lives are now at stake, and Waller is trying to protect her people and save the planet from the worst case scenario they've dreaded since the program's inception.
* SeriesContinuityError: Superman is now able to fly through space without a spacesuit, which, while accurate to the comics, doesn’t jive with this incarnation; he wore a spacesuit in prior episodes because space has nothing for him to breathe.
* ThisIsNotADrill: Said by J'onn to the Watchtower personnel when the [[WaveMotionGun Binary Fusion Cannon]] prepares to fire.
* WideEyedIdealist: After the civilians begin to question the League:
-->'''Green Arrow:''' I'm not sure what I'm doin' here anymore.\\
'''Flash:''' People need us. We help them.
* WorthyOpponent: Even though Captain Atom revealed he is now working for the government and tried his hardest to defeat Superman, Superman insists that Atom is still "one of us" and takes him back to the Watchtower for healing after Superman defeats him.
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