Some things can be counted on at a Slayer recording session. "Can I interest you in something fast and aggressive?" asks producer Greg Fidelman. He's sitting beside guitarist Kerry King at the Pass Studios in Los Angeles, where Slayer are working on a still-untitled album planned for a summer release, and cues up a new metal track with the working title "Build Up." King is ready to thrash.

He's already tapped the Jägermeister machine upstairs, and is now bent over a custom camouflage guitar, his black combat boots on the hardwood floor in the studio control room. King is plugged simultaneously into four amps, each one given a name: The Beast, Hot Ticket Deux, BLS and GF11. Fidelman rolls "Build Up," and King begins overdubbing bits and pieces of intricate metal melody and a harsh, aggressive riff, his eyes closed, nodding to the intense recorded beats of drummer Dave Lombardo. King's strumming hand is a blur, like a wasp in flight.

"Man, I don't even remember it being that fast," King says with a laugh after one take. "We're fucking flying!"

A pair of candles burn nearby, and a large chart lists the songs in progress, most with descriptive working titles, including "7 String," "Drop B" and "Industrial," along with "Psychopathy Red," recorded last October and already leaked online. Slayer are still in the early stages of recording, just five weeks in, working out ideas for what will be an 11-song album, released in July, in time for the summer's second Mayhem Festival tour with Marilyn Manson. Lyrics still wait to be written. Rick Rubin, who produced the band's landmark 1986 album Reign in Blood, is executive producing.

"Why do I write this shit at my age? It's fucking brutal," says King, 44, his head shaved and tattooed. "It's exciting to be part of it and I'm excited to be writing this heavy fucking shit. It's still in the blood."

During this night's session, some friends arrive for a visit. One of them is Rita Haney, wife of the late "Dimebag" Darrell Abbott, and she's brought one of the Pantera veteran's old guitars. It's a blue V-shaped electric from the early-'80s, and she's hoping King will give it a try. "That was his holy grail," she says, handing it to King's guitar tech. She notices a snapshot taped to the Beast of King boozing it up with Darrell and Ozzy guitarist Zakk Wylde. "Ah, the triple threat."

Slayer have survived nearly 30 years since forming in Orange County in 1981, creating the metal-punk collision known as thrash in league with Metallica and other malcontents, inspired by the likes of Judas Priest and Iron Maiden. The band's 2009 album will be Slayer's second with the original lineup since Lombardo returned in 2002, a full decade after his acrimonious break from the band.