As the third installment of the X-Men series opens, the world has entered a relatively peaceful period for mutants. There's a mutant-tolerant president of the United States, a blue furry mutant named Beast (Kelsey Grammer) heading up the Department of Mutant Affairs, and Magneto's shape-shifting femme fatale, Mystique, has been captured. The tranquility is shattered by two events. Worthington Laboratories, using a powerful mutant boy, develops a serum that eliminates the 'mutant X gene' permanently. This so-called 'cure' quickly divides the mutant community; Professor Xavier (Patrick Stewart) and his school are willing to give the government the benefit of the doubt, but Magneto (Ian McKellen) and his mutant Brotherhood see the serum as a vile threat to their way of life. They form an army of mutants and march on the fortified Worthington Laboratory located on Alcatraz Island. A much more dire threat appears in the form of the resurrected super-mutant Jean Grey (Famke Janssen), who ...