K-os was stressing Sam Roberts out. It was January 2004 and the two were collaborating on what would be the genre-fluid song "Dirty Water" for k-os's landmark LP Joyful Rebellion. Alt-rocker Roberts wanted to know if his strumming was sufficient for the Toronto rapper. In separate Zoom interviews the two artistic kindred spirits laugh while recalling how k-os told Roberts, "Don't worry, I'm just gonna flip that shit," before sinking into a sofa at the back of the studio and napping. That left a bewildered Roberts to continue recording "Got Soul but No Money," a song he'd written in the '90s.

"I didn't know what 'flipping that shit' meant when he said it to me about 40 times that day. I do now," a smiling Roberts says while remembering working on Joyful Rebellion, which celebrates its 20th anniversary this year. He assumed k-os would trim lines from the old song he was recording and replace them with a few rapped bars. Instead, k-os unveiled the resonance of what Roberts thought was a throwaway line — "dirty water in my bones" — and weaved something entirely new with his sampler, leaving the alt-rocker floored.

This musical approach was inspired by k-os's time touring with Philadelphia underground rap greats the Roots in 2003, and studying their fusion of hip-hop and live performance. He wanted the same for his next album by sampling musicians rather than only records. The opportunity to do that with Roberts was exciting because his early music reminded k-os of classic rock greats like George Harrison, whose melodies and artful rock sensibility partially inspired Joyful Rebellion.

K-os was impressed and intimidated by Roberts when Linda Noelle Bush, a publisher at Universal who signed them both, played matchmaker. "I could maybe play three chords. And knew my way around a sampler. I didn't consider myself a musician of his caliber… I didn't feel like I could tell [Roberts] what to do," says k-os, explaining his seemingly sleepy standoffish behaviour during the "Dirty Water" session.

Such humility would no doubt surprise fans. That's because Joyful Rebellion singles like "Crabbuckit," "B-Boy Stance" and "Man I Used to Be" would go on to conquer Canadian radio after the album's release. Those songs were blared in supermarket aisles, during the timeouts of live sports broadcasts, and by tastemaking DJs in equal measure because they were so accessible yet singular. The album won Juno Awards for rap recording, single, and music video of the year.

Joyful Rebellion achieved Canadian platinum status, selling more than 100,000 copies. "Those sales figures speak for themselves," says music journalist Michael Barclay, who dove deep into early 2000's Canadian music for his book Hearts on Fire. Barclay adds that, aside from Vancouver's more mainstream Swollen Members, no other Canadian rappers at that point came close to platinum. That success couldn't have been better timed: for a period, k-os insisted his preceding release, 2002's Exit, would be his last. But on Joyful Rebellion's closing track "Papercutz" he spits, "Yo, I know I said I'd exit/ But I couldn't do it the minute/ It flowed from my lips."

Joyful Rebellion's impact can still be felt all these years later: Drake, the country's most successful rapper, invited k-os to his All Canadian North Stars concert in 2022. While there, k-os played "Man I Used to Be" before beckoning Drake onstage for a duet of the rapper's hit "Headlines." Years before Drake broke through the seemingly impenetrable southern commercial border, praise for Joyful Rebellion came from major American outlets including Rolling Stone, Pitchfork, and HipHopDX, the latter comparing k-os' eclecticism to André 3000.

The success wasn't just commercial or international — for Roberts, it was personal. Working with an artist as varied as k-os "changes you because you realize you're wearing your limitations on your sleeve, being like, 'I'm an indie rocker.' Throwing those limitations aside was rejuvenating," says Roberts, adding that this was especially novel in 2004, when genres were more rigid and scenes felt more disparate. There was no going back after that for Roberts, who was inspired to experiment more on his subsequent albums.

Joyful Rebellion co-producer Greg O'Shea calls k-os a pioneer of the rap-singing versatility audiences now take for granted. An Australian producer and engineer trained at Melbourne's famed Metropolis Audio and mentored by Nick Cave producer Tony Cohen, O'Shea has worked with Feist, Tegan and Sara and Gord Downie. He met k-os through mutual collaborators Rascalz, who previously teamed with the rapper on their track "Top of the World." K-os and O'Shea later collaborated on "Superstarr Pt. Zero," off his 2002 debut Exit, impressing the Aussie producer enough to re-join for Joyful Rebellion.

They quickly turned a Toronto rehearsal space into a studio, one so small that the session musicians' instruments sometimes didn't fit in the booth. That off-the-cuff setup and approach led to them creating songs like the swaggeringly catchy "Crabbuckit," which k-os says he intuitively wrote "on the top string of my guitar, like, in 15 minutes." O'Shea then elevated it to an era spanning jazzy jam with upright bass and horn players he knew, along with a drummer who owned a 50-year-old kit.

"We had a real drummer drumming over my sampled beat! It would go in and out of this R&B thing to sounding like, you know, real music" k-os recalls, still sounding gleeful, of how "Crabbuckit" went from sounding current to retro, and ping ponged between genres, thanks to the musicians O'Shea brought in to build on what k-os initially wrote and roughly recorded.

Legendary Motown producer Quincy Jones was his role model when it came to session musicians, k-os says. And of course "Man I Used to Be," is a strong homage to Jones' most famous collaborator, Michael Jackson, with its staccato rhythm and woo-laden chorus. As catchy as that chorus was, it didn't take tons of work. "We recorded that in the rehearsal room that just came out of him jamming," O'Shea recalls. "And I think we both couldn't believe it when those lyrics fell out of his mouth."

Though "Crabbuckit" and "Man I Used to Be" were Joyful Rebellion's biggest hits, k-os was just as proud to hear a cut like "Crucial" on the influential Toronto alt-rock radio station The Edge. "I was one of the first Black artists they played," he says with audible pride about blazing a trail for younger Black musicians. "To me, that's really what the job of being a musician is all about."

One of the rappers k-os inspired was Shad, who rapped while strumming guitar on some of his early songs in the wake of Joyful Rebellion's anything-goes success. To be featured on k-os's 2015 track, "Boyz II Men," was an honour for Shad because Joyful Rebellion was such a touchstone.

"It felt like… the latest and greatest thing to come out of this country in terms of hip-hop," he tells CBC Music via email. "To this day there's nothing like [Joyful Rebellion] — with the exception of his other albums. Back then it made us want to be a fraction as original and dope."

K-os never predicted having such influence. "Some of these guys are better rappers, singers and guitarists than I ever was," he says. K-os doesn't want to just inspire though, he wants to challenge young hip-hop acts.

"My rule is: 'Maybe I can't clear this sample, but I'll use it in a way that no one knows.' I believe in being influenced, but then taking it to the next level. I'm not dissing anybody. I'm not saying they're not amazing. But I just want to have influenced someone, and they be so creative with it that I wouldn't even know."

The most famous artist he has influenced is inarguably Drake, and now they are enjoying a full circle moment as the global star executive produces k-os' forthcoming album (due in 2025).

During Drake's late-2000s ascent, k-os advised him about industry pitfalls, forging a lasting bond. In 2022, Drake asked if k-os was working on a new record after seeing him drop some singles. "He said, 'I'll pay for it, but I need a Joyful Rebellion, classic k-os record,'" k-os recalls of that conversation with Drake, which surprised him because Joyful Rebellion-era budgets are all but extinct.

On Joyful Rebellion, k'os's major label debut, he was mindful of how much money had been invested. "I'd go: 'One for them, one for me. You get a 'Man I Used to Be,' then I make 'Emcee Murdah' for me,'" he says.

In the hopes of re-attaining Joyful Rebellion's career-high water mark, k-os has advice for both himself and other musicians: "A pop song takes 15 minutes. If it's taking days, it could be a great deep cut. But the songs that flourish are quick. That's what I learned from making 'Man I Used to Be' and 'Crabbuckit.' So if you want a hit, it shouldn't take you long."