FUSE TV - Surprise Guests R. Kelly & Billy Idol Dominate Bonnaroo 2013 Superjam

Before it had even begun, it was clear the Bonnaroo 2013 Superjam had a lot to live up to. Not only had last year's all-star jam session featured the return of reclusive R&B star D'Angelo, but Friday night boasted the first-ever hip hop Superjam, a sloppy but knockout concert starring Wu-Tang's RZA and Solange. Even more imposing was Paul McCartney, who owned Bonnaroo just 24 hours earlier. The next day, his lengthy, hit-filled set was all anyone wanted to talk about.

But after Saturday's insane Rock n' Soul Dance Party, it's fair to say the thunder has been stolen from the former Beatle. The core band of the night—led by My Morning Jacket's Jim James and Hall & Oates' John Oates—was a jam-tastic delight in itself, but the special guests were operating on another level entirely.

R. Kelly swung through to croon Sam Cooke's "A Change Is Gonna Come"—which was hypnotically divine—and the blues classic "Bring It On Home," which he naturally left dirtier than he found it. After the R&B star's absurdly cool two-fer, Billy Idol—looking exactly like the punk sneering at you from the cover of Rebel Yell—dropped in and ripped through T. Rex's "Bang a Gong (Get It On)."

Although both singers were Bonnaroo headliners, these appearances were still shocking—keep in mind Kelly and Idol had wrapped full sets of their own just minutes before taking the intimate Superjam stage.

The visual dissonance was incredible to soak in, too. It's hard to say whether seeing Kellz backed by Jim James and his lion's mane hairdo or Billy Idol rocking out next to John Oates and his soul patch was weirder to watch. Let's just say both were beautifully bizarre sights to behold.

Incredibly, neither of those once-in-a-lifetime collaborations were the evening's finest moment. It was the Sly & the Family Stone portion of the night—"Everyday People," "Dance to the Music," "Family Affair," "I Want to Take You Higher," "Hot Fun in the Summertime" and "Thank You (Falettinme Be Mice Elf Agin)"—led by bassist Larry Graham that rocketed the Superjam into the stratosphere. While some of the Superjam songs earlier in the set fudged the line between communal jam session joy and karaoke hokum ("Love Train" comes to mind), these versatile, funky tracks lent themselves to inventive workouts by the technically proficient band.

Plus, Alabama Shakes' soul growler Brittany Howard—another surprise Superjam guest and arguable MVP—was perfectly suited to the Sly Stone tracks, her vocal contributions deftly pitched and sincerely felt. Honestly, it would be a real shame if the Shakes didn't add one or more of these songs into their touring setlist.

By the time it ended with a cataclysmic take on Sly & the Fam's "I Want to Take You Higher"—which found Howard and Idol singing backup vocals—the crowd was as ecstatic as it was stunned. It's not often you get to witness an all-star jam session this unlikely that leaves you so profoundly satisfied.