A super powered being decides mutants have to go and kills off most of them, prompting Professor X and his band of mutant heroes to reveal themselves and try to save the remainder of their kin. Honestly, I'm not sure what the fuss is; maybe I'm just annoyed that Magneto gets killed by a metal object (yes, I know he's not dead). I think Morrison is at his best when dealing with established--but minor--titles. His Doom Patrol was wacky and awesome, while his JLA and this didn't hold my interest, and his personally created work is just drugs and sex. Go back to the Doom Patrol for all our sakes.