It’s not uncommon for an annual to introduce a new character, but it’s pretty unusual for it to introduce the key player in an author’s entire run on a series. That’s what happens here, and true to “Grant Morrison” form, you really wouldn’t know it from reading it. The cover features Wolverine. The story is consistent with the usual X-stories lately: A mutant is being held prisoner by a hostile government and the X-Men save him.
Even the details feel more like Morrison “flavor” rather than critical plot point. The hostile government is China.
So Cyclops learns Chinese.
The team uncovers an underground black market for mutant organs, which are transplanted by an evil corporation to give homo sapiens the powers of homo superior–called U-Men.
John Sublime is a recruiter for that corporation.
The team finds the mutant prisoner, Xorn, who has immense power and is ready to kill himself rather than remain in prison. We are told that his suicide would mean the end of the world.
The team saves Xorn, and he joins.
Xorn’s gonna be really important, and I don’t want to reveal his identity here because this run is so great you really ought to read it.