Def Leppard and Iron Maiden square off in the next round of the Ultimate Classic Rock Hall of Fame. And you'll decide which of these two products of the New Wave of British Heavy Metal has the chance to claim this 100 percent fan-voted honor.

Iron Maiden had, of course, already achieved some notable successes before 1982's 'Number of the Beast,' but nothing like what came next as the group reeled off a total of five straight million-selling discs. Most fans chalk the sudden shift in commercial fortunes to the arrival of Bruce Dickinson, who led Iron Maiden through a sterling run that also included the U.K. chart-topping concert project 'Seventh Son of a Seventh Son' in 1988 before splitting five years later. Dickinson and guitarist Adrian Smith rejoined stalwarts Steve Harris and Dave Murray in 1999, however, and Iron Maiden picked up where it left off. 2010's 'The Final Frontier' streaked to No. 1 in several countries, including the U.K. They've traditionally received little support from American radio, but Iron Maiden has nevertheless scored a series of Top 20 British hits along the way, including 'Run to the Hills,' 'The Number of the Beast,' 'Can I Play with Madness' and 'Be Quick or Be Dead,' among many others.

As with Iron Maiden, the addition of one extra ingredient -- this time in the form of do-anything producer Robert "Mutt" Lange -- hurtled Def Leppard to superstardom. But first, they had to overcome plenty of adversity, not least of which was a car accident that cost the band's drummer one of his arms. They perservered through it all, however, scoring hit after hit in the '80s and beyond with a canny welding of hard rock and hummable hooks. Two of Def Leppard's albums -- 1983's ‘Pyromania’ (featuring the Top 40 hits ‘Photograph’ and ‘Rock of Ages’) and then, after Rick Allen re-learned the drums, ‘Hysteria’ -- sold 22 million copies in the U.S. alone. Into the next decade, Def Leppard completed another multi-platinum effort in 1992's 'Adrenalize,' and they continue to play before sold-out audiences everywhere.

So who moves on to the semifinals? You can vote once an hour between now and Aug. 17, 2014 at 11:59PM EST. The next inductee will be announced on Sept. 2. Be sure to read our official rules.


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