Abigail Brand is investigating an orbital lab when she is attacked by the Brood. As her damaged ship speeds towards a collision with Earth, the X-Men mount a rescue. They are successful but Emma thinks she sees her long dead student, Wallflower, milling around in the gathering crowd. When she tries to make contact, Laurie transforms into a giant flesh Sentinel.
The X-Men battle a giant flesh Sentinel that has emerged from the body of Wallflower--an old teammate they believed to be long dead. Things get worse when the Sentinel shoots Brood aliens out of its fingertips. Once the Sentinel is destroyed, Abigail explains that someone has used Beast's post M-Day research to reanimate and genetically modify dead mutants and send them against the X-Men.
As the X-Men try to figure out who is attacking them using genetically modified dead mutants, a huge cross between a Brood and Krakoa the Living Island assaults their base. After the threat has been neutralized, the X-Men go up in a rescue vehicle to try and find the source of these mysterious attacks. They discover a huge cloaked ship and Wolvie and Armor get them on board. At the heart of the ship, they find it is run by the head of Paradigm, a mutant who fell to the Phalanx more than ten years before.
The X-Men are on a giant ship that seems to be the source of strange genetic mutations culled from the DNA of dead friends and foes. While Cyclops yells at Beast for letting his research get stolen and causing all of this mess, the rest of the team finds themselves battling a cross between Sauron and the Brood. The X-Men ride in the ship as it returns home so they can confront the mysterious mastermind behind their current difficulties.
The X-Men finally confront Kaga, the villain who has been reanimating their dead friends and foes and weaponizing them to attack. He turns out to be a bitter old man who hates the X-Men for being attractive and powerful while his own mutation has left him ugly and feeble. After he concedes defeat, Wolvie horrifies his teammates by punching the old guy in the face to keep him from activating his "Wheelchair of Death."