Having discovered the hidden Sentinels headquarters, the X-Men find themselves under attack by various defense weapons. The ground where they are standing quakes and boulders crash down on them. The X-Men use their abilities to get to higher ground; Angel grabs Xavier, Beast can easily go up the hill, Jean levitates herself, Bobby creates an ice-ladder and Cyclops shoots himself hand- and footholes as he climbs up the cliffside.
Up at the plateau they are momentarily safe since they are out of firing range, but Xavier points out that the Sentinels will investigate sooner or later and that they need to invade the fortress before any other defensive equipment is activated.
Iceman creates a small glider with two poles for himself and the Beast, then Cyclops uses his optic blast to shoot the construct over the gap towards the fortress. At first the glider is doing fine, but shortly before reaching the fortress it starts to tremble since its design isn’t aerodynamically accurate.
Angel departs to rescue his teammates but before he can reach them, Hank and Bobby are captured by tentacles coming out of the fortress. They are being pulled in and as Warren tries to go after them, a flameblaster is activated and the Angel can’t enter the opening. Inside both Hank and Bobby are thrown into a glass-cube filled with sleeping vapor.
Bolivar Trask, creator and captive of the Sentinels, can’t do anything to stop the robots that are operating the defensive weapons. He tries to reason with them but they repeat their deduction that to safeguard humanity they have to rule it.
He then is brought to the Master Mold, an even bigger robot that sits in the main room and acts as their central command center. Master Mold has the power to create more Sentinels but not the necessary knowledge. He blackmails Trask by threatening to destroy half the US if he does not help with the construction.
Outside the remaining X-Men wonder what to do as Xavier comes up with a new plan. He knows that he can’t control or guide a mechanical mind, but maybe his mental energies are enough to disturb them. Straining real hard he reaches inside the fortress and causes the defense weapon operating Sentinels to temporarily shut down.
Other Sentinels nearby know that the most logical thing to do would be to replace their comrades, but they aren’t allowed to make such a decision without their section leader, who is currently busy with another group of robots that have to bring the Beast into Master Mold’s chamber for interrogation.
Jean, Scott and Warren can enter the fortress without problems. Inside they meet a Sentinel whose programming has given him no commands for facing additional mutants. The robot orders the X-Men to follow him as it wants to ask the section leader how to respond to the situation. The X-Men think that they are finally onto something and decide to follow, at least for now.
(partial flashbacks)
In the Master Chamber Dr. Trask is forced to place Hank McCoy under a mental Psycho-Probe. The ray will make the Beast reveal his innermost secrets. Hank starts and explains that he is one of the X-Men and that their purpose is to protect mankind from evil mutants and any others dangers.
Upon hearing this Dr. Trask is ashamed about how wrong he was about the young mutants.
The Beast continues about his parents. His father worked as a laborer for an atomic plant and probably that is why his son turned out to be a mutant. Growing up Hank learned one day of his special powers when he was almost hit by an approaching car and leapt to safety with his powerful legs.
Meanwhile the X-Men are led deeper into the fortress and pass the room where Iceman is still held in the glasscube. Immediatly they try to get him out, but that is something that the Sentinel can not allow. He attacks but Marvel Girl and Angel make him topple and fall, while Cyclops shatters Iceman’s prison. The X-Men have back one of their members but the incident sets off all alarms inside the headquarters.
(partially flashbacks to the Beast’s origin)
Inside the main chamber Master Mold believes that his Sentinels are able to deal with any threat and continues the interrogation of his prisoner.
Hank narrates that he was always very good at school, but in sports he exceeded everyone. One day during a public football game he became overenthusiastic and showed his powers as he kicked off his shoes and leaped onto the goal post. The press reported of the unusual athlete and not before long a stranger contacted the McCoy family and offered to train the mutant boy in the use of his powers.
Outside the fortress Xavier was mentally following the psycho- probing and decides that Master Mold might not gain any more information like his name or the school’s location. He telepathically overrides the Beast’s mind and prevents him from continuing with his origin.
Master Mold recognizes that an unknown presence is in his chamber and floats the room with micro-electric blasts that are able to hurt the professor’s astral self. Xavier is forced to retreat and re-enter his body before fully discorporating, he makes it outside the fortress but is about to collapse a few feet before reaching his physical body.
By now the other X-Men have been cornered by a group of Sentinels. Iceman creates a thick wall to protect his teammates, but one of the robots uses his propulsion unit to smash through. Left with no escape route all X-Men fall prey to the section leader’s heavy gravity beam.
