While en route to help young Cyclops, Bobby is attacked by a mysterious assailant but is rescued by Cable, who urges him to flee. Iceman refuses but is incapacitated and captured while Cable is killed. Young Jean attempts to use Cerebro to locate Bobby but states that she is unable to find him. In a secret lab, the man who attacked Bobby is revealed to be a time-displaced version of Cable who has him locked up in a tube. Kitty gathers all of the X-Men, who split into four teams tasked with protecting one of the remaining time-displaced X-Men. Young Jean uses her telepathy to guide her team to young Cable's base, where he admits to murdering his older self because he had failed in his mission to maintain the timeline by allowing the young X-Men to stay in the present for so long. They discover that Cable has been genetically modifying young Iceman so that he looks the way he looked when he left his original time period. He releases Bobby and teleports them all to Atlantis, where Ahab is attempting to kill young Cyclops so that the timeline can never be restored. The X-Men find themselves overwhelmed by Ahab's forces and Cable convinces the young X-Men that they must return home immediately in order to save the others. Young Iceman breaks down to his older self, admitting he doesn't want to be forced back into the closet but the present day Bobby tells him that his younger self finally allowed him to accept that he was gay and promises that he will be finally be able to truly be himself when he grows up. Cable then sends the X-Men back to their original time, informing them that everything will return to normal once they officially close the time loop. In 1964, the young X-Men change into their original clothes and young Jean performs a mind wipe so that they won't remember their time in the present day although she informs them that she is able to lock their memories away so that, once the loop is closed, their older selves will regain those memories. Back in modern day, the founding X-Men inherit the memories of their younger selves allowing them to defeat Ahab. Returned to their original time, the young X-Men forget about their adventures in the present and are greeted by Professor Xavier.