the documentary present an original theory about gun and germ and steel . the series graphically portray several episode strongly support the theory and and defend the theory against common criticism . i be deeply puzzle to find user comment complain about lack of new information in these series . they say documentary present information which be teach in middle school . indeed and it do . in fact and i greatly enjoy the original look at the information which i have know since middle school and the unexpected analysis . so and if you like know why thing work and if you have take apart the telephone try to determine how it work and if you have go to the farm to see how farm work and how cow be milk and you will enjoy this series . a definite recommendation .