The X-Men storm into Xavier’s office as they hear the loud alarm from Cerebro. Cyclops wants to keep them out since his teammates have not been filled in on the apparatus yet, but Xavier says that the time for having secrets is over. He briefly explains that Cerebro is a mutant brain wave detector and according to the device’s loud reaction, they are about to face one indescribably powerful opponent. The professor already suspects who it might be, but time is running short and so he orders his students to build some defenses outside the mansion.
Following their mentor’s orders the team rushes out; Iceman surrounds the area with ice-walls, Beast and Marvel Girl lay some cable traps and Angel fills some logs that have been hollowed by Cyclops‘ optic beams with grenades.
Five minutes later the team again assembles in Xavier’s study. The professor has switched off Cerebro, since it was too loud to bear, and now he decideds to fill the team in that he thinks their unknown attacker might be his brother. He never mentioned him before, but now it is inevitable and so he starts the story at the beginning.
(In the past)
Years ago, when Charles Xavier was still a child, his father Dr. Brian Xavier had been killed during an atomic blast at Alamagordo, New Mexico. Even though his colleague Dr. Kurt Marko comforted Xavier’s widow Sharon, young Charles never trusted him and months later he knew why, when Marko proposed to Sharon Xavier. After they married it became clear that Marko only cared for the wealth and money of the Xavier family.
One day Cain, a son from a former marriage showed up. He got expelled from school and now he had to live with the Xaviers. Being a few years older than Charles he had no problems in beating him up occasionally.
(Now)
Xavier switches on the detection device again and the beeping is even louder than before. Obviously the foe is almost at the mansion. The X-Men run to a window and see that the icewalls are smashed down. The whole mansion is trembling and furniture falls. Xavier continues his story.
(In the past)
Not before long Sharon Xavier died of a broken heart and young Charles was left alone with the two Markos. One day he overheard a conversation in a lab during which Cain accused his father of having created the atomic accident on purpose to gain Xavier’s fortune.
Charles comes out of his hiding place and a fight starts. Some lab equipment breaks apart causing and explosion and a fire. Kurt Marko pulls both boys out of the room shortly before dying of having breathed fumes and fire.
(Now)
A brilliant light is seen through the window. A cvertain sign that the attackers has reached the second line of defense, the cables that emit an electro-magnetic forcefield. Yet he is not stopped, his hands are seen snapping the cables.
(In the past)
Not much later Xavier started to discover his mutant power of telepathy. He believes that the genetic material of his parents had been altered by the radiation during which they were exposed while doing nuclear research. While his powers developed his hair started to fall out. Charles Xavier became a prize pupil in every subject as he could always pull the right answers from his teacher's mind and even in sports events he could predicts his opponent’s tactics.
With every success his stepbrother got more and more jealous. Cain started to beat him up again, but now he had no chance as Charles was able to mindread his blows and could dodge them. Weeks later the brothers were driving to a vacation when Cain lost control of the car. Charles was badly hurt in the accident and even today he still can feel the shock and pain of the accident.
(Now)
The figure outside the mansion reaches the third defense ring and the grenades launch from the hollow logs. Sleeping gas fills the air, and even though would be enough to stop a herde of elephants the villain marches on. Xavier continues his tale as he now explains how Cain Marko became superpowered.
(In the past)
Years later the brothers both served in the Korean war, Xavier as a medic and Marko as a soldier. By coincidence they worked in the same area and as the other side was firing explosives, Cain deserted and ran away.
Xavier followed him into some caves and inside the stepbrothers discovered an anient temple of Cyttorak. In the middle there was a giant glowing ruby and Cain picked it up and read the inscription. “Whoever touches this gem shall possess the power of the crimson bands of Cyttorak ! Henceforth, you who read these words, shall become ... forevermore ... a human Juggernaut !“
Cain started to change right before Xavier’s eyes, but suddenly the caves were hit by bombs and the ceiling started to give in. By hairbreadth Charles got out of the mountain in time, while Cain was buried under the rubble. Further research revealed that Cyttorak magically empowers his follower and that the Juggernaut is a force that irresistbly moves forward crushing everything in his path.
(Now)
Seeing the figure approaching the mansion, the X-Men enforce doors and windows with steel plates. Suddenly one plate buckles inward and at last it breaks. Iceman erects another icewall, but it is smashed with one punch. The whole team attacks as one, but the Juggernaut is unimpressed; he simply tosses the teenagers aside and now now he is fully seen ( huge figure, muscular body, brown costume with a giant helmet) as he stands in front of his stepbrother, about to attack.