Two of the biggest animated slackers around, Beavis (Mike Judge) and Butt-head (also Judge) get a kick-start when two crooks steal their TV. On their mission to find a replacement, Beavis and Butt-head wind up in the motel of Muddy Grimes (Bruce Willis), where a case of mistaken identity has them after his wife, Dallas (Demi Moore). Due to misunderstanding Grimes when he says to "do" his wife, the two travel from Las Vegas to Washington, not realizing they've been sent out to kill the woman.