When Black Sabbath veterans Ronnie James Dio, Tony Iommi, Geezer Butler and Vinnie Appice — collectively known as Heaven & Hell — released The Devil You Know on April 28, 2009, no one could have guessed that they would soon be speaking in the past tense about their beloved singer, who died of cancer the following year. 

Some even doubted if the quartet’s only studio full-length under their new legally mandated name would boast the musical and aesthetic credentials to qualify it as a bona fide Black Sabbath album. But it did.

After all, Heaven & Hell were indeed Sabbath by another name: the second most celebrated formation of the iconic heavy metal godfathers, and the lineup behind 1981's Mob Rules and 1992's Dehumanizer. This foursome reunited for a third and final time in 2005, initially simply for touring, after years of Iommi and Ward waiting for Ozzy Osbourne to join them for another visit to the studio. Who could blame them for finally taking matters into their own hands, making their peace with Dio and Appice, and finding a clever workaround to using the Black Sabbath name, now co-owned by the Osbourne camp?

Certainly not the thousands of fans who flocked to Heaven & Hell concerts over the ensuing years. This response spurred the quartet to commit new music to tape – first with three new songs for the 2007 Black Sabbath compilation The Dio Years, and then in the wee months of 2008, with the full-length album The Devil You Know. And still, of amid the heated and widespread conjecture surrounding the album’s imminent release, the fundamental question boiled down to something like: “Which Black Sabbath would show up?”

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The answer was something familiar and distinctive: a musical marriage made in hell (in the best possible way!) conjoining the snail-like pace of Black Sabbath’s earliest years with Osbourne at the helm, the incremental majesty and more considered, thought-provoking wordplay typical of those first two Dio-fronted LPs (Heaven and Hell and Mob Rules), and, finally, the ungodly power chord heaviness fine-tuned by Iommi during his “wilderness years” as Black Sabbath’s sole remaining champion.

To put it another way, imposing doom anthems like "Atom and Evil," "Fear" and "Rock and Roll Angel" essentially paid due on the promise made, oh, nearly a quarter-century earlier, by the Dio / Iommi / Butler / Appice lineup’s previous comeback album, Dehumanizer. Moreover, with the occasional bursts of energetic head-banging conveyed by tracks such as "Eating the Cannibals" and "Neverwhere," The Devil You Know seemed to conclude what, for countless Black Sabbath fans, had felt like unfinished business when their previous reunion had collapsed under such dispiriting and almost embarrassing circumstances years earlier.

Above all else, though, Heaven & Hell’s triumph represented a rare victory of musical artistry over musical branding, since everyone but the most uninformed and blindly unquestioning Osbourne sycophants eagerly embraced this alternately named edition of Black Sabbath as the real thing.

All of which made Dio’s terminal cancer diagnosis, just months after The Devil You Know’s release, all the more tragic. He battled the disease with his usual class and dignity until May 16, 2010, when it finally claimed Dio. Still, no one could ask for a loftier musical epitaph than Heaven & Hell’s The Devil You Know.

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