Professor Xavier warns the X-Men about an impeding event that wipes half the mutant population: Nitro will self-detonate in Genosha. The Brotherhood rescue Nitro from a government prison against his will and use Psylocke to control him, planning to use him as a weapon. The X-Men chase the Brotherhood in order to prevent Genosha's destruction.

Wolverine and Mystique fight Maverick and Sabretooth to protect Maverick's daughter Christie. Wolverine discovers some pieces of his past at Weapon X.

When the M.R.D. creates mutant hunting Sentinels, the X-Men and the Brotherhood team up to take down them, and Master Mold, down.

In the future, Marrow has developed a strong friendship with the re-programmed sentinel.

Jean Grey has been abducted, but as the X-Men begin the search a new problem arises. Magneto has forced the hand of Senator Kelly into launching a Sentinel attack on Genosha so that he can strike back and begin the war! Meanwhile in the future, Mastermold has captured Xavier and is forcing him to reveal the locations of mutants all over the world!