Xavier experiences a flashback to when he investigated a “telepathic scream” coming from a Mayan ruins. The tunnels were filled with hieroglyphs of aliens. At the end of the tunnel, he finds two women battling an alien entity, a “Synraith”. Gracie Gamble and Cuckoo are grateful for Xavier’s help in banishing the entity back through the portal. They are safe until the “next dimensional alignment”. But in Xavier’s best interests, Gracie decides that his memory should be erased, lest “he will never be able to feel safe again”.
Xavier awakens in present day Westchester. Scott, Jean, Warren, Hank and Bobby have decided to take a day trip into the city. Jean is worried about Xavier and offers to stay but he does not want to ruin her day.
Sam wonders if he could tag along to the “one night comeback o’ Bernard the Poet”. But the camaraderie of the original five X-Men is quite exclusive, and they hint to Sam that he has not yet earned his place among the senior X-Men. As they drive away, Bobby feels a little sorry for them being harsh on Sam.
In the “remote Guyana Highlands” of Venezula, Gracie Gamble and her team finds another ancient ruins of alien origin.
In the English village of “Ravenscroft”, superhero twins Rory and Pandora are on their way home from school. They decide to eavesdrop on their “elders” on whether they will be allowed to “fight crime”.
The elders of Clan Destine, Walter, Adam, Samantha, Kay and Dominic are in the conservatory. They catch the twins spying on them. Kay’s surprise project of her “astral form” scares the twins away. Rory and Pandora manifested too early, and the elders are debating on whether to train them by allowing them “occasional crime patrols with one of [them] chaperoning”, or split them up because “their abilities stimulate each other when in close proximity”. But the elders soon start fighting amongst themselves as Walter does not think his siblings and father are responsible enough to take care of the twins.
Cannonball is in the Danger a Room training with Storm. Wolverine is already in the Danger Room and decides to hang around. Suddenly a portal opens and pulls Cannonball in. But he manages to blast free of the force. The portal closes but Wolverine senses that the alien entity is still present.
After the quarrel, Kay and Samantha seek Dominic’s help. Dominic is resting under the ruins of the old manor. Suddenly the twins appear, as does Walter and Adam. Walter does not like that the twins have wandered into this unsafe building. He starts arguing with Kay again. Dominic, still wanting to take a nap in peace, leaves them.
Gracie wanders into the ruins and finds that the “dimensional rift is already forming”. She summons her usual spell but the Synraith “has tricked [her]” into “feeding the portal” instead.
Forge has been called in to examine the Danger Room but cannot find anything wrong with the systems. Wolverine was certain he sensed something else other than Shi’ar technology at its best. Suddenly, Xavier is psychically attacked and the “dimensional rift” opens. Xavier, Storm, Wolverine, Colossus and Forge are pulled into the rift.
Back at Ravenscroft, Kay suddenly goes into a trance-like state. Suddenly, the rift opens and Kay, Samantha, Walter and Adam are pulled in. Walter manages to push Domimic, and the twins out of harm’s way, but Rory insists on showing off and rushes towards the rift to save his family. Rory gets trapped in the pull. Walter manages to break free once again and saves Rory, Samantha and himself. But Kay and Adam disappear into the rift.
In the Danger Room, Wolverine, Storm and Forge have broken free of the rift’s pull. Just then, Cyclops, Phoenix, Archangel, Beast and Iceman return after Phoenix “sensed the Professor’s psychic distress”. Wolverine wants to jump into the rift after Xavier but Cyclops commands him to wait until the portal has been properly analysed.
At Ravenscroft, Newton has come to help Clan Destine analyse the portal and trace Adam and Kay. Walter decides the the twins can tag along on the rescue mission because he does not “trust [them] to stay out of trouble”.
Xavier and Colossus find themselves in a wasteland.
After Forge makes some calculations and preparations, the X-Men are ready to enter the portal.