The X-Men face new perils in their “Muir Island Saga.” At the heart of this chapter, the enigmatic Warren (later revealed as Mystique in disguise) returns and claims to have been cured. When Xavier, Cyclops, and Jean fail to recognize him, tension and suspicion ripple through the team. In the shadows, Apocalypse’s forces start closing in—and an unexpected betrayal might be closer than anyone realizes.