When Def Leppard's Pyromania was released in 1983, the Sheffield band was still playing club-sized venues in the U.K. As radio and MTV leaned heavily into the album's singles, the band's popularity exploded, and, in turn, the venues they played expanded, too.

Four decades years later, the group is looking back at its career, starting with its earliest days, in a new book, Definitely: The Official Story of Def Leppard. The band digs deep into its archives, working with Genesis Publications over the past two years to sort through piles of photos and band-related ephemera. 

The book is loaded with photos; you can see some of them below. But there's also an extensive oral history that covers Def Leppard's timeline album by album. "It was like doing a documentary," guitarist Phil Collen tells UCR in a recent conversation. But, he adds, "Most books are past tense. We're still current, touring and actively putting out records."

Collen, who joined the band during the Pyromania sessions, outlines some highlights from the era when Def Leppard became worldwide stars below.

The success of Pyromania
"When that album got going, it exploded so quickly. The first gig at the Marquee [on Feb. 9, 1983] ... I’m from London, so I’d played there so many times with [my previous band] Girl. We actually had a residency there. So it was like playing my front room with my buddies. I knew all of the guys in Def Leppard, so it was cool. It definitely wasn’t intimidating. But when we got going, we were shocked at the success of it, especially when we got to the States. My first American show was the Omni in Atlanta, Georgia, opening up for Billy Squier. But we were still an opening act, so I’d done that before. I’d opened for Kiss, UFO, ZZ Top and lots of different bands before that. But it was shocking more than anything else, the rate that things went [with Pyromania]. With MTV, we kind of looked more like Duran Duran than we did Judas Priest. So you had this different appeal going. A lot of things clicked when that record came out."

Listen to Def Leppard's 'Stagefright' 

The guitar solo for "Stagefright" was recorded in a single take
"Mutt Lange is an honor to work with. It’s like going to school with your favorite subject. He would just know things and he’d get you to sing things that were out of your range. He’d get you to play stuff that you couldn’t actually normally play. He’d [be encouraging] and go, 'Yeah, you can do that. I heard you sing that before. You can sing that. So more than anything else, you ended up not wanting to disappoint him. There was this wonderful vibe and groove going. I’d met Mutt before because I knew the guys [before Pyromania]. I think they were doing High ‘n’ Dry when I first met Mutt. They were in the rehearsal room just working some songs out. So I knew the vibe, and that was kind of cool, you know? It slotted in straight away and he was so friendly and inspiring. He’d say, 'Have a listen to this song.' It was 'Stagefright' and he said, 'Take it home and think of a solo.' I came in the next day and that was the only first take on the album apparently. I just plugged my 50-watt head into the speaker cabinet that they already had miked up and boom, away you go. The next thing I know, we’re on tour. It was crazy."

Def Leppard played with two drummers before Hysteria was released
"It was all about making Rick [Allen] feel comfortable [after his accident]. Jeff Rich [from Status Quo], who Rick chose, it was just in case the electronic stuff broke down. Because we didn’t know back then. Jeff missed one of the shows - he missed a flight and got there late, and Rick just carried on and it was totally fine. The [shows with both drummers] were cool. It was a little bit weird. It was cool playing with two drummers, but it was even better when it was just Rick, obviously. It was like, 'Ah, the gang’s back together!'"

How a motel burglary made Phil Collen stop wearing a shirt onstage, leading to a new look
"It was in Ft. Myers, Florida. I was in a motel-type thing on the beach and someone just walked up, knocked the door down and took all of my shit. I had no clothes, nothing. I borrowed things - I had a pair of flip-flops and Union Jack shorts, and that was it. These kids at the next show said, 'We’ll take you to the mall.' So I went to an Army surplus store and got some camo pants. That was it. That was the kind of look, really, for a while. It just felt more comfortable. And you know, I’ve always stayed in shape, so that wasn’t a problem. Also, I used to sweat a lot. I don’t seem to sweat as much now. I’ve kind of got it down, but I’d be dripping [after the shows]."

Watch Def Leppard's 'Pour Some Sugar on Me' Video

The magic moment when Phil Collen found his chemistry with guitarist Steve Clark
"I think the main thing is that there’s so many guitar players in two guitar bands that both play exactly the same thing and it’s a little bit amateur. If you see an orchestra, they’re playing counter-rhythms, countermelodies, everything [in that vein]. So we decided to do that. We obviously took a leaf out of Brian May’s book. You know, the Queen stuff was orchestrated. We got into this guitar orchestration thing and especially with Mutt Lange there, he’d be pushing that agenda forward. We’d be doing, like, 16 guitar parts on one thing. Not gratuitously, but making them work with the vocals and the song. We kind of set out on a mission. There was so much of that on Hysteria. It was really great to utilize two very creative guitar players that you would think would play very differently, but you could actually put them together and you’d get all of these different things coming out that would support the vocal and the narrative. It was really cool. Once we hit on that, it was like finding gold, for both of us."

Definitely: The Official Story of Def Leppard

The band looks back at four decades of history.

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