The Civil Wars are over, the Superhero Registration Act has passed and the mutant population is growing again after M Day.
And Weapon Plus has once again branched into America to begin Weapon XVI, a step beyond the goals of Weapon X.
Weapon XVI is searching for a way to control mutation, to create living weapons and to cure the rest.
Mutants are being rounded up and placed in concentration camps. They are divided into two groups: the expierments and the useless. The useless are killed and harvested for their DNA, while the expierments are further mutated until they are literally living weapons.
The X Men are furious and are trying to halt the program peacefully. Magneto, the Brotherhood, the Hellfire Club, and the Morlocks have other ideas however. And Mr. Sinister is secretly helping the program, posing as Dr. Windsor to further his own research.