The event concludes a storyline that began in November 2012 during Brian Michael Bendis' run as writer on All-New X-Men, a series that debuted as part of the Marvel NOW!
Following the conclusion of All-New X-Men, the story of the time-displaced original five continued in X-Men Blue, which saw them working under the tutelage of Magneto with Jimmy Hudson and Bloodstorm, developing new relationships in the modern day, most notably Angel's relationship with Wolverine, Iceman being outed as gay, Beast experimenting with dark magic, Cyclops reuniting with his father and trying to come to terms with the actions of his future self and Jean Grey coming to terms with her own deaths and subsequent resurrections.
[3][4] In the lead-up to the event, all current X-books were cancelled and had special post-credit scenes added to them by Extermination writer Ed Brisson and artist Oscar Bazaldua.
[5] In Chicago, the young X-Men rescue a pair of mutant children from a mob of violent anti-mutant protestors and take them to the X-Mansion where they are checked over by Cecilia Reyes.
In a secret underground lab, the attacker reveals himself to be a younger version of Cable who locks Iceman inside a tube and resolves to find the other four original X-Men.
Ahab invades the mansion and an enraged Prestige charges at him but he easily bests her and uses the two mutant children to enable him to take control of Old Man Logan.
[7] Young Cyclops is frustrated at having been taken to Atlantis by Nightcrawler, X-23 and the adult Jean Grey but she refuses to allow him to take the fight to Ahab and promises to protect him in their underwater base.
Ahab uses the children again to take control of Nightcrawler and Shatterstar but Jean and Cannonball manage to save the young Cyclops and Marvel Girl from their attacks.
[10] Prelude Main Series Aftermath A review by Mike Fugere of CBR states that Extermination was "mostly" fulfilling for readers who had been following the story of the time-displaced X-Men for six years but felt it was "a bit rushed", using the analogy of a television network cancelling a show and leaving its showrunners to "swing for the fences and condense what would be a season's worth of content into a handful of episodes".
He did, however, agree that "with so many X-Men coming back from the dead or being shuffled about, the mutant landscape has gotten pretty damn crowded in recent months" and therefore "getting rid of duplicate characters makes sense", summarising that "if this final arc was simply a way to sweep things aside to make room on the shelf, then writer Ed Brisson and artist Pepe Larraz handled things pretty well".
It turns out the story of the time displaced original five X-Men might have come to a close, but the next chapter in comics' greatest superhero soap opera is just beginning.