Ed. Note: A dozen years ago this week, Jay Z and R. Kelly teamed up for what was supposed to be an album worth of classics from two titans of the hip-hop and R&B worlds. What resulted was an uneasy tension that erupted in a nasty incident two years later and led to a rift that has still yet to truly cool off. Twelve years after the album that kick-started it all, we look back at the beginnings, tensions and legacy of the beef.

Back before the "Ignition" remix, before Beyoncé and Blue Ivy, two titans of industry, R. Kelly and Jay Z did the unthinkable and teamed up to release a duo of albums that would result in one of the most disastrous moments in hip hop.

Initially, it seemed like a great idea. Their first collaboration was when R. Kelly cheerily crooned the hook on Jay Z’s “Guilty Until Proven Innocent.” Accused of stabbing his former business partner Lance "Un" Rivera, the song was Jay's vocal rebuttal to the media’s portrayal of him as nothing more than a guilty crook. When Jay returned the favor on R. Kelly’s “Fiesta (Remix)” and suddenly found themselves with a smash hit collaboration, the proposition was made for the two to record an album. After all, Kels and Jay seemed to complement each other with a silver-tongued delivery that was destined for success.

Prior to release, The Best of Both Worlds was speculated to become nothing short of a blockbuster for the duo. But just weeks before it officially dropped, on March 26, 2002, the Chicago Sun-Times received a now-infamous sex tape purported to feature R. Kelly and a minor. Public damnation quickly ensued and their label, Def Jam cut promotional efforts and shied away from the release. The Best of Both Worlds was strangled in its crib.

Not that a dump truck full of posters, TV appearances, music videos and tours would have made things much better. The Best of Both Worlds was rife with flaccid, topical lyrics that failed to resonate with listeners and critics alike. Even a brief shining moment of brilliance in “Shake Ya Body” wasn’t enough to carry the album. Merely a year after Jay Z released his magnum opus, The Blueprint, fans were left scratching their heads and wondering where things went wrong.

Two years and an indictment on 21 charges of child pornography later, Kelly had dusted himself off as best he could and was riding high on the platinum-selling success of 2003's Chocolate Factory. The chart-crushing “Ignition (Remix)” highlighted the indelible talents of Kels. His cooing, suave delivery on the party anthem was everything that The Best of Both Worlds wasn’t.

After sharing the stage at Jay Z’s not-so-farewell concert in 2003, the duo scrapped together tracks left on the cutting room floor from the TBOBW sessions for the Unfinished Business album and mapped out a tour of epic proportions.

Perhaps this is where the wheels really fell off.

Jay Z complained about Kelly’s lack of concern for rehearsing and frequent tardiness. Kelly complained about Jay Z’s lighting crew leaving Kels in the shadows. The entire tour was plagued with insecurities, including Kelly allegedly getting into an altercation with the lighting director during a St. Louis show. It was a clash of two personalities that recognized the utter brilliance in one another but struggled to find common ground for creative purposes. The emotional fragility of Kelly is what gives his songs such an earnest, heartfelt gravitas. The business-minded Jay Z keeps a razor-sharp focus on moving onward and upward in his career. An unwavering boldness with a languid delivery that doesn’t have time to fuck around.

Everything came to a head at the now-infamous October 29th, 2004 Madison Square Garden show. Mere minutes into the performance, R. Kelly abruptly left the stage after claiming to have seen an audience member wave a gun at him. Whether someone actually waved a gun or not, no one else saw it happen. Twenty minutes later, Kelly headed back to perform, but it was too late. The butting of creative heads and conflicts just couldn’t bear the weight anymore between the two.

While Jay Z denies having anything to do with it, one thing is certain; as Kelly attempted to climb back on stage, he was met with a face full of pepper spray from a member of Jay’s crew. Kelly took a trip to the emergency room and was removed from the rest of the tour in a haze of "he said, she said" and multimillion dollar lawsuits.

Nearly ten years since that incident, and a dozen since The Best Of Both Worlds, the two are in pretty much the same places they left off. Jay still sits on top of the rap world, except now he’s wealthier, rapping about fine art more often than fine women. Meanwhile, R. Kelly continues to be dogged by the same allegations he faced and was acquitted of at trial in 2006, while still captivating the R&B world that is able to turn a blind eye, most recently with last year's Black Panties album. The lawsuits have dried up between the two, but there remains little common ground.

Two of the greatest musical talents of this generation recorded two albums worth of music together but never truly coalesced as the duo they wished to become. No matter how bad we wanted it at the time, in the end, it looks like the world never needed it. —Brett Koshkin (@Bkoshkin)

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