By 2001, Linkin Park had swiftly and skillfully amassed legions of fans. On their low-key hilariously titled DVD Frat Party at the Pankake Festival, one unnamed shirtless fan sums up the band’s appeal: “They’re the shit because there’s nobody else that’s better than them.”

Statistically speaking, he was correct: The band’s debut, Hybrid Theory, sold nearly 5 million copies that year, bolstered by nonstop radio and MTV play, and became the best-selling album of 2001. Linkin Park seized the moment, landing the Ozzfest main stage that summer in the midst of a global tour. Nearly 90 shows across four continents: That’s a lot of time on the tour bus. How were these six young musicians — who blended hip-hop and electronic elements into their industrial hard rock — to spend it?

They kept working. Using a homemade mobile studio in the back of their bus, producer/songwriter Mike Shinoda, a ProTools surgeon, kept tinkering with Hybrid Theory and eventually recast its harshness as something more subterranean. The following summer, that patchwork came alive as the remix album Reanimation, released 15 years ago on July 30, 2002.

Reanimation plays like an alternate-reality Hybrid Theory, headphones music for staring out the bus window. Notably, it splices the band’s trademark broiling screams from Chester Bennington - who died on July 20 and whose raw vocals defined early hits “In the End” and “Crawling” -- for more rhymes. And not just from Shinoda, the group’s emcee, but via a cadre of underground rappers, the kind not likely on the radar of the prototypical Linkin Park fan in 2002. Jurassic 5’s Chali 2na, Pharoahe Monch, and The Roots’ Black Thought all feature on beats crafted by guest producers like Alchemist, Evidence, and DJ Babu. They inspired Shinoda; this is how he paid tribute.

From the beginning, Shinoda’s cerebral rhymes separated Linkin Park from their nu-metal peers. He opted for pensive menace (“Things aren’t the way they were before/ You wouldn’t even recognize me anymore”) instead of Fred Durst-style misanthropic party-starting. Behind the boards, Shinoda immediately proved himself a mechanic who understood and respected hip-hop: Listen to “In the End” for proof.

Then listen to how it’s transformed on Reanimation. Hear KutMasta Kurt’s reworked stuttering beat on “Enth E Nd” (for this album, even track titles get remixed). Hear how Motion Man’s rhymes nearly make Bennington’s essential hook an afterthought. Keep listening to experience Shinoda flex and talk s--it over the crackling, vinyl crate-born backbeat of “H! Vltg3." By the time Chali 2na enters “Frgt/10,” it’s easy to forget this is a Linkin Park album at all. Its interlude-laden tracklist most resembles the big-scale hip-hop releases of that era, like The Eminem Show and Stankonia. Indeed, Reanimation is the sound of Linkin Park giving back to the genre they lifted from, as Dan Weiss wrote in a recent Stereogum remembrance.

Of course, not everything on it sounds like a gift today. The album is marred by its inescapable 2002-ness. Remember the scratch-tastic X-Ecutioners, who collaborated with Linkin Park on the quintessential rap-rock time capsule “It’s Goin’ Down”? They’re here, though all they do is mash up Hybrid Theory riffs explored more creatively elsewhere on the album. “Kyur4 th Ich” suffers the same fate and ends up a stale remix of an already inessential track. If meticulous editing yielded Reanimation, these songs deserved prompt deletion.

The same goes for some of the set’s rock tunes -- which it does have, by the way. “By Myself,” a brutal, assaulting Hybrid Theory cut, does not require an update, and yet we get “By_Myslf,” which dulls its sharpest tool (Bennington’s scream) for more stodgy guitar noise courtesy of Deftones’ Stephen Carpenter. “Wth>You,” oppositely, doesn’t feel different enough from its source material.

However — and this is important! — Reanimation is likely the only album in existence to feature members of both Jurassic 5 and Staind. And while it certainly celebrates hip-hop, the nu-metal heavyweights that complete the guest roster are not to be overlooked. Aaron Lewis brings the syrupy “Crawling” rearrangement to its emotional climax. Korn’s Jonathan Davis lends his manic aggression to a gauzy, stretched-out “1stp Klosr.” Stephen Richards of Taproot offers a new vocal melody to “P5hing Me Aw*y,” which came to replace its namesake on future Linkin Park tours. Even Orgy’s Jay Gordon handles a remix himself (“Pts.OF.Athrty,” released as the set's lead single, with a music video that got heavy MTV2 play). Coupled with the rap features, these heavier numbers slapped Reanimation with a rigid rap-rock tag, and their success allowed Linkin Park a way to push their sound forward on 2003’s Meteora — and beyond.

If Reanimation was the batting cages, Collision Course, the 2004 JAY-Z/Linkin Park collaboration album, was Yankee Stadium. After proving they could work alongside rappers and that they understood the schematics of the genre (including its commercial staying power), Linkin Park was apparently contacted by Jay-Z for a potential team-up; shortly after, we got “Numb/Encore,” the Grammy-winning partnership that ultimately made both songs definitive. Collision Course signified rap-rock’s highest post-TRL peak, and helped keep JAY-Z in the spotlight even after his post-Black Album “retirement.”

It helped Linkin Park, too, in finding a sustainable course forward, as alternative metal relented to more melodic pop on the charts. 2007’s Minutes to Midnight embraced a softer musical palette (“Shadow of the Day” is one of Bennington’s finest performances), with electronic influences they’d continue to pursue up to and including on their latest album, One More Light. And since then, they’ve continued expanding their roster of hip-hop collaborators: This year’s “Good Goodbye,” featuring Pusha T and Stormzy, is certainly an EDM song and wouldn’t sonically fit on Reanimation, but it retains that album’s spirit of cross-genre partnership.

The post-Reanimation world also coincided with a rise in what journalist Simon Reynolds calls “record-collection rock” in Lizzy Goodman’s book Meet Me in the Bathroom -- that is, music made by those with a deep knowledge of multiple genres and niche history, made possible by the internet. Imagine a parallel universe where Vampire Weekend’s Ezra Koenig found inspiration in Nine Inch Nails instead of Talking Heads, then married that with his admiration of A Tribe Called Quest. You probably wouldn’t get Reanimation, but you might get something close to Meteora. You might also get an utter catastrophe.

And that’s the point. Fifteen years (and another remix LP) later, it’s clear: No one could’ve made this album, still the top-selling hip-hop remix album ever, except Linkin Park and their Rolodex of co-conspirators. That’s time very well spent on the tour bus.