Charles Brady (Brian Krause) and his mother, Mary (Alice Krige), are the last of a dying species of supernatural felid shape-shifters known as "Sleepwalkers." They feed on the lifeforce of young virgin women and can only be harmed or killed by domestic cats. Moving into a small Indiana town under false identities, Charles targets a high school classmate, Tanya Robertson (Mädchen Amick). While attempting to feed on Tanya to keep his mother alive, Tanya fights back, setting off a violent struggle where the local police and an army of neighborhood cats converge on the Brady home.