The definitive history of heavy metal and what it’s always been about.

A metal fan crowd surfs in a mosh pit during the heavy metal festival Wacken Open Air in Germany. (Philipp Guelland, DAPD/AP)

Heavy metal — rock’s dark side — tends to draw a bright line through music fans, through any crowd.

People run to it, or they run away from it. Fans hear majesty and hard, dark truth. Un-fans hear rage and noise. Fans hear nuance — power metal, thrash metal, black metal, nu metal. Un-fans hear menace. Well, they should. To a point.

Up next On Point: A big new oral history works through the roots and meaning of heavy metal music.

-- Tom Ashbrook

Guests

Jon Wiederhorn and Katherine Turman, authors of "Louder Than Hell." (Greg Cristman/HarperCollins)

Jon Wiederhorn, co-author of "Louder Than Hell: The Definitive Oral History Of Metal." He's senior writer at the rock and heavy metal magazine Revolver. (@LouderThanHell)

Katherine Turman, co-author of "Louder Than Hell: The Definitive Oral History Of Metal." She's a music journalist and producer for "Nights With Alice Cooper." (@KatherineTurman)



Robb Flynn, lead vocalist and guitarist for the heavy metal band Machine Head. (@TheGeneralMH)

A Conversation With Machine Head's Robb Flynn

Flynn described Machine Head's typical audience, saying, "They were just there to vent their anger in a healthy way, and we were there to give them a soundtrack to do it."

Flynn also revealed the tragic story behind the song "Aesthetics Of Hate," which he wrote after the on-stage murder of Pantera's guitarist:

Book Excerpt

Excerpted from "Louder Than Hell: The Definitive Oral History Of Metal" by Jon Wiederhorn and Katherine Turman with permission from It Books / HarperCollins Publisher.

Playlist

Advisory: The following songs contain explicit content.

Tweets From During The Show

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From Tom's Reading List

Definitive Metal Family Tree

NPR: China's Artist Provocateur Explores New Medium: Heavy Metal — "The man ArtReview magazine named the most powerful artist in the world is trying his hand at rock stardom. In 2011, the Chinese artist Ai Weiwei spent 81 days in detention. He was later let go and charged with tax evasion. Now, he has released his first heavy metal song, based on his time in police detention."

The Guardian: Rocking On: When One Heavy-Metal Frontman Is As Good As Any Other -- It is hardly a high-risk strategy to replace one incredibly famous singer with another, but there must surely be an element of defiance in the move, as if the remaining Pilots are saying: "Well, the last thing we need is another preening berk with a hot temper. Let's go for someone utterly inoffensive this time." Whether or not this new collaboration works and leads to more commercial success for the hardy grunge survivors is another matter, but at least Bennington won't be guzzling heroin and thumping people for looking at him a bit funny."