Kid Omega's latest scheme to set up his own mutant school goes horribly awry when mysterious aliens called The Remaining kidnap his "students," demanding a rare Phoenix Egg-source of the awesome Phoenix Force-in exchange for their lives. Wildly out of his depth, Kid Omega turns to Cyclops for help. He gets a ride with space pirates the Starjammers, and someone more responsible: Cyclops' brother Alex "Havok" Summers. Their mission: rescue the students, recover the Egg, save the day. But it won't be easy. Galaxy-hopping sleuthing, heists, and action lead the X-Men into a fight with the Shi'ar Empire, and a monstrous plot to unleash the Phoenix Force and conquer the galaxy.