As he prepared to film his 1984 heavy-metal mockumentary This Is Spinal Tap, director Rob Reiner, not much of a metalhead, attended a Judas Priest concert. He wasn’t prepared for the raucousness he stepped into. “It physically hurt my chest,” said Reiner, as quoted in This Is Spinal Tap: The Official Companion. “The reverberation in the hall was so strong that I couldn’t stay there any longer.”

Reiner picked the right band to help him get a grip on the state of the art of heavy metal at the time. Black Sabbath and Deep Purple were the pioneers, but no group exemplified the genre quite as thoroughly as Judas Priest. The band represents an extra-loud branch of the hard-rock family tree coming into its own, and it’s hard to find a more enthusiastic booster for the music than frontman Rob Halford. The 67-year-old singer, who joined the band in 1973, has watched headbanger culture become deeply ingrained in music culture.

“We were one of the first British heavy-metal bands to come to America in the very early days of metal and tour extensively,” Halford tells the Scene, speaking by phone in his rich British accent. “[We would] play every bar, play every club, play every venue we possibly could to lay out the roots of metal.”

In the mid- and late 1970s, when Judas Priest was making its way into the U.S., there weren’t a lot of acts for the band to tour with that sounded much like them. “We would open up for bands like REO Speedwagon and Head East and Molly Hatchet,” Halford recalls. And while he thought all of those bands were great, they were hard-rock, not metal, bands. The members of Judas Priest recognized that they were something else entirely, and quickly embraced their role as ambassadors for metal, exposing American rock fans to the harder-edged music being blasted on the other side of the pond.

“You know what it’s like when you see that you’ve got something good in you?” Halford asks. “You really want to get out there to people and want them to experience something that really means the world to you as a band. If it’s connecting, that’s like a dream come true.”

Being around in the genre’s primordial period gave Judas Priest a blank canvas to create its own image of heavy metal. In the beginning, the band had something of a post-hippie stage presence, with costumes that included velvet bell-bottoms, wide-brimmed hats and silk capes. In short order, the group traded those threads in for a more menacing image. Halford adopted the leather and metal studs that became the band’s signature look, an image assumed by metal bands ever since. Their sound underwent a similar evolution. Priest’s early records were fueled by bluesy acid-rock with hints of prog. But with each passing record the band got fiercer, and by the end of the ’70s, they’d stripped down to Halford’s searing snarl, which he could turn into an operatic scream at will, along with dueling guitars and a ferocious rhythm section that thundered through tighter, catchier songs.

This was the sound that sent Reiner running for the exit, and the one with which Judas Priest began to find commercial success. Priest’s fifth album, 1978’s Killing Machine (Hell Bent for Leather in the U.S.), saw the group score its first two singles on the U.K. charts (“Take on the World” and “Evening Star”). There was fresh blood on the cutting edge: Iron Maiden, Motörhead and Def Leppard were forging the new wave of British heavy metal movement, a headbanging parallel to the art-school aggression of punk in the U.K. But Priest had helped lay the groundwork those groups were building on, and the work of the younger groups in turn was a major inspiration on thrash metal, the next evolution to come to prominence.

Priest’s next LP, 1980’s quintessential British Steel, reached the No. 4 slot on the U.K. albums chart and marked the band’s entry into Billboard’s Top 40. It was the first of seven of the band’s albums to repeat that feat throughout the ’80s. The group became emblematic of metal in popular culture, from multiple references on The Simpsons, to Beavis and Butthead becoming fans of “Painkiller,” to a ’90s Burger King ad campaign featuring “You’ve Got Another Thing Coming.” The band’s rabid fans were even the subject of the 1986 cult-classic documentary short “Heavy Metal Parking Lot.”

Neither the recognition nor changes in the lineup over the years — one key change involved Halford leaving the band in 1992, though he returned in 2003 — has softened Judas Priest’s approach. In 2018, the band released its 18th studio album, Firepower. The album was produced by Tom Allom, with whom the group made the bulk of its classic material in the ’80s, and its 14 tracks scored high marks from an array of metal publications. It also came close to matching the performance of British Steel in the U.K., hitting No. 5 on the albums chart.

Longtime guitarists K.K. Downing and Glenn Tipton are no longer with Priest. Downing left in 2011, and Tipton retired from touring in 2018 following his public announcement of his diagnosis with Parkinson’s disease. But Halford and bassist Ian Hill — who recommended that the band give Halford a shot when it was looking for a singer way back when — are heading out this spring, with longtime drummer Scott Travis and seasoned guitarists Richie Faulkner and Andy Sneap rounding out the lineup.

And don’t worry: Halford hasn’t traded in his leather and studs for anything more comfortable, or less provoking.