Iceman, Lorna Dane, Angel and Havok are arrested by Sentinels and his leader Larry Trask. Beast, Marvel Girl and Cyclops are looking for them, using the mini-cerebro machine. Approaching the Sentinel HQ, their ship is struck by a missile, but they manage to survive.

Meanwhile, inside the building, the Sentinels are restraining Larry Trask because he's also a mutant (his medallion was used to block his abilities and to avoid sentinels detecting him). In a monitor, we saw Sentinels capturing Quicksilver, Scarlet Witch, Toad, Blob, Mastermind and Unus.

As the Sentinels are about to start killing the captives, Cyclops, Marvel Girl and Beast enter their HQ. Cyclops has a plan and they change clothes with Quicksilver, Scarlet Witch and Toad to confuse the Sentinels.

Larry Trask's mutant powers begin to emerge, and he sees the future - Havok's death - and then tells Judge Chalmers to use a strange pistol on Havok.

Beast and Jean continue fighting Sentinels, while Cyclops splits up to look for his brother. A Sentinel attacks Cyclops with a ray, but Judge Chalmers jump in front, taking the blast. The Sentinels change their priority to protect the injured human. Cyclops frees his brother, who can't control his powers and his energy levels begin to rise dangerously. He runs away before detonating a huge explosion.

Cyclops realizes that the Sentinels are bound by logic, and convinces them that they have to destroy the source of all mutation, so they all fly off towards the Sun and are destroyed by the heat.

Afterward, the X-Men find Havok in a state of shock, and call a doctor - Dr. Lykos - a friend of Professor Xavier, to try to cure him.