Equipped with telepathy-proof helmets, Jean Grey’s X-Men, the Avengers and Namor’s Atlantean army mean to take down Cassandra Nova and free her hostages. Cassandra has sent the brainwashed prisoners to fight for her. Jean protects her side telekinetically from their bullets. The heroes put ant-telepathy helmets on their foes, freeing them one by one.
Jean shouts they need to get control of the heli-carrier in the air and they need to lure Cassandra Nova out in the open. Honey Badger tells her she’s out. As Cassandra hovers above her army, Jean reminds her people not to hurt the other side, just get the helmet on them.
Cassandra flies away upward. Is she running? Captain America asks. Instead, Cassandra creates a hole in the heli-carrier’s hull and enters. When the soldiers aboard protest, she simply murders them, then strides toward the nuclear reactor.
From outside, the heroes see an explosion. Trinary tells them one of the carrier’s six nuclear reactors was just compromised. The carrier is in catastrophic failure. Cassandra is bringing it down on Genosha. They realize this will destroy the island and kill them all. Iron Man points out that the problem is the amount of radiation coming from the breached reactor. They can’t get near. Ignoring him, Gentle asks Nightcrawler to teleport him up there.
Nightcrawler teleports himself and Gentle high up in the air above the carrier, so Gentle can drop on it. He hits the breached part of the hull and begins closing the hole.
On the ground, Trinary informs the others that the radiation levels are falling. Captain Marvel asks in disbelief if their guy is holding together a reactor with his bare hands. He probably is, Jean agrees. She gives the order to evacuate the carrier and then get it away.
That moment, the Magneto helmet lifts from her head and floats upward, where Cassandra Nova is hovering. Jean thinks she can keep her out of her head? She snarls. She won’t be ignored, she threatens. Jean tells Storm to evacuate the carrier and the Avengers to keep freeing the civilians along with the Atlanteans. She warns them not to engage Nova. She will tear them apart with a thought!
What’s to stop her from doing that to Jean? Captain America asks. Jean retorts that she is trying right now and she is still here. Jean flies toward her and both of them lash out at each other with their psychic powers.
In the meantime, Storm leads several X-Men and Avengers in steering the carrier away from the island. Iron Man suggests dropping it into the water and letting the explosion go off into the sea. King of the sea flying right here, Namor reminds him unamused.
Gambit figures he can use his power to charge things to paradoxically prevent an explosion. He orders everyone off deck.
In the meantime, Cassandra has Jean lying on the ground. She tells her that’s where her kind belongs - in the ground. Laura Kinney attacks her from behind, slashing at her.
Gabby tells Nightcrawler they are up. Kurt is not happy but Gabby promises she won’t feel anything. Does she have it? he asks. Be super awkward if she forgot their secret weapon, she shoots back. He tells her to hold her fist like they practiced. She complies and he mutters this is stupid. Only if they fail, Gabby insists.
Cassandra lashes out at Wolverine with an energy blast. She pieced herself together from almost nothing! Cassandra boasts. And she thinks she can be stopped by being stabbed? Laura retorts that she thinks Cassandra can be mildly distracted by being stabbed.
Before Cassandra understands, Kurt teleports Gabby onto her back. Gabby stabs into her head and reaches into the back of her skull.
In the meantime, Storm, Namor, Captain Marvel and the X-Sentinel evacuate the humans from the heli-carrier.
Gambit begins to charge up the walls. He turns to Thor whom he asked to stay behind and asks he assumes Thor can stand a bit of radiation. The thunder god replies he has ventured to the dreaded realms of Sprague and withstood the skin-flaying gasses of the Balyeg Beast. Confused Gambit asks if that is appliable to the situation. Thor remarks it is actually an aptly comparable experience. Gambit tells him to get Gentle who stayed behind and then come back for him.
Thor soon finds Gentle literally straining to hold the core together. Addressing Gentle as “mighty warrior,” he tells him it is time to go. Gentle groans he can hold it. Thor puts a hand on his shoulder and assures him he does not doubt that. He believes he could hold the jaws of the World Serpent open and stand between it and Armageddon. But it’s alright. He can release his grip. He can let go.
On the ground, Cassandra lashes out, pushing back Gabby. She cannot be killed so easily, she announces darkly. Jean replies, they weren’t trying to kill her. Gabby left a surprise behind in her skull. One of her nanites is now in her skull, reprogramed by Trinary. Every time their minds touched, Jean felt there was an integral part of Nova missing. Nova is horrified as Jean informs her that they have given her what she was lacking. Now, every time she feels a mind, she will feel something else. Something she has never felt before. Empathy.
Aboard the carrier, Gambit tells Gentle and Thor that, if he has done this right, all the energy will blow up harmlessly into the sky. And if he got it wrong? Gentle asks. They’ll be torn apart before he feels any embarrassment.
He got it right and Thor flies away with the two of them.
On the ground, Casandra stammers. Jean tells her she put herself together and she was put together wrong. For all her power, she was a pawn to the hatred she was born with. She is far from the first to grow up with a prejudice she didn’t understand.
“What have I done?” Cassandra asks horrified. She caused a lot of pain, Jean replies, but she doesn’t want Casandra dead, she wants her healed. And then she wants to help her atone. She knows what it is like to be driven by a destructive force. To be consumed by vengeance. She offers Cassandra her hand. She wants to show her her vision.
Later, Jean, Kurt Gabby and Laura stand outside the United Nations building in New York. Kurt asks Jean if she is ready. She is, Jean replies. Gabby tells her to go in there and blow their minds! The others look at her quietly. Seriously? Laura asks. Gabby makes it worse by explaining her joke, then amends that Jean should go in there and be inspirational without any diplomat heads exploding.
Soon Jean holds her speech inside the UN, flanked by X-Men and Avengers. She assures them mutants are nothing to be afraid of. They are not the enemy. The only enemies are those who seek to divide them. The ugly bullies who decry their differences rather than celebrate their similarities. Who set them against each other for their own political gain. “We are not the enemy. We are you.” She died. She returned to a world divided. A world where intolerance is celebrated and ignorance is cheered. Where rumor is fact and fact is dismissed. She doesn’t believe in this world. She believes in a greater one. They are all stronger than this, better than this, kinder than this. She believes they can evolve past this point in history. She believes they can build a finer world together. She’d like to show them a world where no one is left behind…