The award-winning television series Mystery Science Theater 3000 (1988-1999) has been described as the smartest, funniest show in America, and forever changed the way we watch movies. The series featured a human host and a pair of robotic puppets who, while being subjected to some of the worst films ever made, provided ongoing hilarious and insightful commentary in a style popularly known as riffing. These essays represent the first full-length scholarly analysis of Mystery Science Theater 3000--MST3K--which blossomed from humble beginnings as a Minnesota public-access television into a cultural phenomenon on two major cable networks. Included are interviews with series creator Joel Hodgson and cast members Kevin Murphy and Trace Beaulieu.