The Pearson family, led by Nana Rose (Doris Roberts), rents a lakeside house for a summer vacation. The family includes Uncle Nathan (Andy Richter) and Stuart (Kevin Nealon), father of the family, and the children, especially teenager Bethany (Ashley Tisdale) who has a boyfriend named Ricky Dillman (Robert Hoffman) who ends up as a robot under the control of the mysterious aliens. Bethany’s brother Tom (Carter Jenkins) is a computer whiz and geek overall who can oppose any invader from space. The family is disrupted when four miniature aliens, led by Tazer (Thomas Haden Church) land in their attic, using mind control on the adults before launching a major invasion of the planet. Children cannot be controlled by the aliens, and thereby hangs the fate of the world.