As justly famous as Def Leppard has become, there are still plenty of lesser-known facts hidden away in their platinum-plated career. This new video explores everything from the unique spelling of their name to their long-ago first gig, from the weird happenstance that led to tragedy for one of their stalwart members to the lingering riddles inside one of their biggest hit singles.

Well before Def Leppard began packing arenas everywhere in the '80s, it seems they once smuggled beer into a much more intimate venue for the band's debut appearance. You'll never guess where, and how. Speaking of head-scratchers, we dug deep into Def Leppard's liner notes in search of a mystery man who joined them on keyboards for 1983's breakthrough smash Pyromania. The name, familiar to early viewers of MTV, might surprise you.

Did you know that long-time drummer Rick Allen could potentially have walked away miraculously unharmed from a scary December 1984 accident that took his left arm – if not for a terrible twist of fate? We'll also share the forgotten story of the lost first single from Def Leppard's 1987 mega-hit Hysteria.

Finally, we sort through the mysteries of the group's 1988 No. 2 U.S. hit "Pour Some Sugar on Me," with help from founding frontman Joe Elliott. Spoiler alert: There may be some parts even he can't explain.

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