Sentinels attack Los Angeles searching and killing all the persons with mutant genes. This action of the government happens after Magneto, a man that can control the magnetic field of the Earth, and his Brotherhood of Mutants explode a bomb in Capitol Hill and goes to television to say that they, the Homo Superior, will decimate the human kind and replace it. Meanwhile, in San Diego, a man with huge feet and hands is watching TV in a bar when another customer starts picking on him. He tries not to get in a fight, but he has no choice than defend himself and knock the other guy out. But he is the one to get a shotgun pointed to his head, just because he is a mutant. When he leaves a girl makes him an offer that he can't refuse.
In Athens, Texas, the same girl enters a police squad and, using her powers, makes the deputy think that she's a Federal Agent and makes him take her to Ororo Munroe, a car thief that, after being caught by the sheriff, started a lightning storm. She quickly gets her out of there.
Finally, on New York dockside a Russian mafian gets nailed while exchanging a nuke and has to reveal his ability to turn his body into organic steel. While Piotr Rasputin is waiting for the Sentinels to get him, he is invited by the girl to join the X-Men.
In Salem Center, a reformed school, the group gets together and they are introduced to Scott Summers, also known as Cyclops. Scott asks the other classmates for their nicknames and Ororo introduces herself as Storm, Piotr as Colossus, Henry McCoy as Beast and Jean Grey as Marvel Girl. They go to meet the Professor and are surprised to see that he can talk thru their minds. When Colossus asks how Professor X found him, he introduces Cerebro, a device he and he former friend, Magneto, created to amplify the Professor powers and lets him find humans with the mutants gene. He uses it again and finds the location of a boy, Bobby Drake that ran away from home scared that his parents might get hurt when the Sentinels discovered that he's a mutant. He sends his X-Men to Times Square to find the kid. But when Beast discovers him, Sentinels attack them. Beast rescues Bobby before any harm is done but
they have to fight the Sentinels. While Cyclops gives orders and Beast runs thru the buildings with Bobby, Storm creates a lightning storm and hits 3 sentinels, impressing Cyclops, but she faints. Beast destroys two more using their guns against themselves and Colossus destroys what was left of a half destroyed Sentinel, but he is hit by the only one standing. Cyclops distracts him and he's grabbed, but easily dispatches the Sentinel. While
Marvel Girl stops Cyclops fall, the Sentinel is about to some watchers, but Bobby saves the day by freezing it, earning the nickname Iceman from Beast. Surprisingly, the persons they saved start hitting them and they have to run for it.
In the Savage Land, Magneto sees the TV report about the group of mutants that saved the humans and says that his old friend Charles is behind it. Quicksilver, Magneto's son says that the armdealers arrived and Magneto goes to them. We discover here that the nuke Colossus was exchanging was bought by Magneto, but when they lost the nuke, Magneto uses his power to remove the peacemaker the man has thru his chest and making him an example to
everyone. Finally, he decides to assassinate Charles, and says that the best person to do this is Wolverine...