On July 2, a giant alien mothership enters orbit around Earth and deploys several dozen saucer-shaped 'destroyer' spacecraft that quickly lay waste to major cities around the planet. On July 3, the United States conducts a coordinated counterattack that fails. On July 4, a plan is devised to gain access to the interior of the alien mothership in space, in order to plant a nuclear missile.
On the first day at his new school, Cameron instantly falls for Bianca, the gorgeous girl of his dreams. The only problem is that Bianca is forbidden to date until her ill-tempered, completely un-dateable older sister Kat goes out, too. In an attempt to solve his problem, Cameron singles out the only guy who could possibly be a match for Kat: a mysterious bad boy with a nasty reputation of his own.