Almost five months before Metallica released Kill ‘Em All, Metal Blade owner Brian Slagel saw Slayer open a show for Bitch at the Woodstock Theater in LA. Blown away, he asked the band if it would submit a track to his upcoming compilation album Metal Massacre III. They agreed and when he heard the song they turned in, “Aggressive Perfector,” Slagel offered Slayer a record contract. On Dec. 3, 1983, the band released its scorching debut, Show No Mercy.

Many assume Slayer were influenced by San Francisco bands including Metallica and Exodus, but they just happened to share many of the same influences, including Judas Priest, Iron Maiden and Motörhead, as well as punk rock acts like Black Flag and The Exploited and early thrash they heard through underground tape trading networks.

“We were doing the same thing at the same time as Metallica, so it wasn’t really groundbreaking when we first heard [Metallica’s] No Life ‘Til Leather [demo],” frontman Tom Araya told me in 1998. “It was more like, ‘Dude, check out this tape. Who the hell is this? They sound kinda like us.’ We were tripped out.”

“I was just getting out of the metal thing with Priest and Iron Maiden, and I was listening to a lot of hardcore when we started,” said late guitarist Jeff Hanneman. “I was into the punk, but still loved the metal, and Kerry was into metal, and when we started writing together those influences all came together.”

Slayer wrote many of the songs for Show No Mercy before they were signed, including “Die by the Sword,” “Black Magic” and “Tormentor.” The rest were hashed out before the band entered the studio in November 1983. While the record is fierce and served as a major kick in the ass to other speed metal bands to ramp up their tempos and ratchet up their level of aggression, the production was sub-par, largely because it was produced by an engineer at L.A.’s Track Studios and recorded in a single week.

“We did it every night from 11PM to seven in the morning,” Araya said. “It was the only time this guy could get away with charging us next to nothing. We paid him for his time and for the tape. ‘Here’s a $400 check.’ We spent $1,500 for it in total. Kerry borrowed money from his dad to pay for half, and I paid half.”

In addition to upping the ante on speed metal, Show No Mercy was one of the first thrash records to include such blatantly Satanic lyrics and imagery: “Satan, our masters in evil mayhem guides us with every first step / Our axes are growing with power and fury, soon there’ll be nothingness left,” Araya growled on “Evil Has No Boundaries.” And on the title track he sang, “Hold high his name, we must / Warriors from the gates of Hell, in Lord Satan we trust.”

Venom was an influence on Kerry at the time, and that’s part of the reason why a lot of the stuff came out the way it did,” Araya recalls. “Also, Mercyful Fate was starting up around that time and they sang a lot about evil. We were really into that.”

“It’s something we stumbled onto and we all dug,” added guitarist Kerry King. “I don’t believe in any kind of religion. It’s all as dumb as can be, but I really like horror movies and they kind of go hand in hand. People ask why we make songs about Satan. Why does Stephen King write horror stories? Why is Clive Barker a sick bastard? It’s just your way of expressing s--t. The world is not a vase full of roses.”

A month after Slayer handed Slagel the master tape, Metal Blade released Show No Mercy. Despite having no time to properly promote the album it quickly became the label’s best-selling release. Four years after it came out, Metal Blade reissued the disc and attached the three songs from the band’s 1984 three-song EP Haunting The Chapel. When Show No Mercy was released again in 1994, the label added “Aggressive Perfector,” but included just one song from Haunting the Chapel -- “Chemical Warfare.”

“It was definitely the birth of the Slayer sound,” Araya said. “When it came out we listened to it compared to everything else and we thought, ‘This f---ing rocks.’ The only think we kept saying was, ‘Next time let’s do everything a little faster.”

Loudwire contributor Jon Wiederhorn is the co-author of Louder Than Hell: The Definitive Oral History of Metal, as well as the co-author of Scott Ian’s autobiography, I’m the Man: The Story of That Guy From Anthrax, and Al Jourgensen’s autobiography, Ministry: The Lost Gospels According to Al Jourgensen and the Agnostic Front book My Riot! Grit, Guts and Glory.

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