Metal Evolution presents 11 episodes based on the much-debated Metal History "family tree" originally shown in Headbanger's Journey. This 24 sub-genre genealogical chart reveals the vast complex progeny of heavy metal--from Early Metal and Shock Rock to Thrash, from Progressive Metal to Grunge and Nu Metal. Using the chart as his road map, our host, metalhead turned anthropologist Sam Dunn, will crisscross the globe in search of the very essence of Metal, from bars and back alleys to the biggest open air festivals.