Men cannot resist her. Mankind may not survive her! When a creature, geneticaly engineered through extraterrestrial intelligence, escapes from observation, scientist Xavier Fitch (Kingsley) assembles an elite team of experts to track it down. The crew - a government assassin (Madsen), an empath (Whitaker), a biologist (Helgenberger) and an anthropologist (Molina) - combines their expertise and traces their prey to Los Angeles. There, in the form of a stunning young woman (Henstridge), the alien initiates a horrific plan to mate with unsuspecting men and produce offspring that could destroy mankind. As her deadly biological clock rapidly ticks, Fitch and his team are hurled into a pulse-pounding chase in which the fate of humanity itself lies in the balance!