Ronnie James Dio appeared tired but happy after the Mob Rules lineup of Black Sabbath – touring under the name Heaven and Hell – completed their 2009 world tour. He didn't know, however, that their Aug. 29, 2009 performance at the House of Blues in Atlantic City, was going to be the last.

Dio originally regrouped with Tony Iommi, Geezer Butler and Vinny Appice to record three new songs for the 2007 Black Sabbath compilation album The Dio Years. They then decided to stay together and begin touring. Finding a warm welcome from audiences across the globe, the newly named Heaven and Hell kept working. By 2009, they'd released an album, The Devil You Know.

“We toured Japan as part of our last trek and went out for dinner,” guitarist Iommi later explained in his usual underplayed manner. “We began chatting and had a few drinks. Someone said, 'Does anybody fancy writing a new album?' and everyone replied, 'Yeah, that's an idea. Why don't we do that?' Really, that's how The Devil You Know started.”

In another interview, he noted that the "new songs we’ve been playing have been going down very well. ‘Bible Black,’ ‘Fear,’ they’ve been going down very well.”

Watch Heaven and Hell Perform 'Bible Black' at Ronnie James Dio’s Last Show

The tour in support of The Devil You Know started on May 5, 2009. During their visit to the Wacken festival in Germany, Dio demonstrated his everyman demeanor when asked if the size of an audience changed his approach to a show.

“It doesn’t matter how many people are out there; it’s never just another gig,” Dio said. “I prefer to play smaller places myself, only because you don’t have the personal touch with an audience this big. The person who’s number 70,000 who’s waving at the back, I can’t see him or her. ... Most musicians prefer to play for people they can see and they can feel. Part of the experience of being a musician, with any crowd, is being able to have some kind of connection with them.”

Asked whether he and Iommi were aware of their status as “legends” and “inventors of heavy metal,” Dio said: “I think we’re well aware of it because, all the shows that we’ve done, with all the bands that have been on the bill, they’re so respectful of us, and they do say things like, ‘Without you … [and] you’ve done so much wonderful things.’ But we try not to listen to it that way. Once you start to be praised and you believe that, I think you become less of a person. Then you start believing what they say: ‘I’m so important.’ Neither Tony nor I feel that way.

"Geezer and Tony and Ozzy [Osbourne] and Bill Ward were the ones who really invented this form of music," Dio added. "I’m glad to be able to be part of it. It’s a great point of pride, but I think you can’t let it be too prideful or you lose all control over yourself. You think you’re better than you are.”

Watch Heaven and Hell Play ‘Children of the Sea’ at Ronnie James Dio’s Last Show

That attitude, along with the fans’ appreciation for their work, kept Heaven and Hell together beyond what they had all thought would be a one-off reunion. After taking his last bow at the tour’s end, Dio announced that the group wanted to keep going – though a hiatus would be necessary while Iommi underwent hand surgery.

“It was tiring,” Dio said of the tour. “Every show was great, as always. This band is never not great. It was very productive. We’ve been on the road for such a long, long time, even thought we took some time off to do what I think is a great album. It was all very concentrated and very difficult to do at times, but the music made all the difference. The shows we did made all the difference. I guess all in all I’d give it nine and a half out of 10.”

Asked if it was the start of something rather than the end, Dio replied: “It is, of course. When you’ve done such good things over a long period of time, and you’ve been good at it, you think, ‘What am I going to do when I get home? Maybe we should have done more.’ Of course, there’s always sadness for that. But we’ll do more. We’ll be doing another album, and I’m sure we’ll do another tour.”

Watch Heaven and Hell Perform ‘Mob Rules’ at Ronnie James Dio’s Final Show

His plans included a European tour with his own band Dio, set to take place during November and December 2009. “I’ll be able to get home for Christmas Eve and go, ‘Bah humbug!’” Dio joked.

“After that a lot of it depends on Tony, what happens with his hand operation and how long it takes to recover. But he’ll be fine; it won’t be a problem at all," Dio said. "It’s a matter of time and space, and for me, I know nothing else other than to play. That’s what I do, that’s what I love to do. Dio’s a great vehicle for me. I love the people in that band; I always have and I always will. It will always be something that I will do. So, yeah, I got a lot more things to do.”

Watch Ronnie James Dio Interview From His Last Heaven and Hell Show

None of that was to be. After the Dio tour was cancelled, his wife and manager Wendy announced on Nov. 25, 2009, that “Ronnie has been diagnosed with the early stages of stomach cancer. We are starting treatment immediately at the Mayo Clinic. After he kills this dragon, Ronnie will be back onstage, where he belongs, doing what he loves best, performing for his fans. Long live rock 'n' roll, long live Ronnie James Dio. Thanks to all the friends and fans from all over the world that have sent well wishes. This has really helped to keep his spirit up.”

Even though Dio vowed “cancer, I’ll kick your ass,” he died on May 16, 2010 at age 67, with all those plans unfulfilled.

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