After her high school graduation in 1960, Ginny Drummond left her small town in Iowa, vowing never to return. Years later, though, she attends her 50th class reunion -- an event with life-changing ramifications for her and William Fairchild, the classmate who befriends her. The reunion is momentous for all their classmates because of an anonymous letter and its contents promising riches to the last surviving member of their class. Ginny and William initially believe the letter to be a joke, but things soon turn deadly because someone will stop at nothing to be the last in the class.