And just like that, Kendrick Lamar's To Pimp a Butterfly album has turned five. Laced with jazz, fury and Afrocentric raps, the LP earned universal acclaim from critics and has been deemed by fans to be the most important project of K. Dot's career.

While TPAB definitely left its mark on Kendrick's loyal fan base and the music industry as a whole, the imprint it left on the collaborators who contributed to the project is just as indelible. "If people ask me what's the greatest hip-hop album ever made, [if they] ask me, it is TPAB," says Rapsody, who provides a guest verse on "Complexion (A Zulu Love)." She is the only rap guest verse featured on the good kid, m.A.A.d city follow-up. "It's so powerful what he did with this album."

The power Rapsody speaks of is something others involved with the LP could sense as they were in the Top Dawg Entertainment trenches putting it together. "The things that were happening during those sessions and just how locked in everybody was, Ali, Sounwave, just everybody, it was a moment in time you knew like, 'Ahh, this feels like really, really special,'" says Rahki, a TDE-affiliated producer who crafted both the album's lead single, "i," and "Institutionalized."

For his part, Rahki remembers controlled chaos and K. Dot's level of engagement with the project. "Kendrick is such a quiet type of artist, I don’t think the general public really knows like how involved he is in every beat, every session, every…Like, he’s really a genius and it’s just him every day," recalls the producer, who bounced between two studios to help create "i." "It felt like madness, but a good madness."

Another person that can attest to the frenetic pace of TPAB sessions is famed jazz pianist-producer Robert Glasper, who says he played on nine of the album's songs, with eight of his contributions being delivered in a single day. "[Kendrick] kept saying, 'Pull up this song,' 'Pull up that song, play what you hear,'" remembers Glasper. "So he would pull up a song and I would just learn it real quick and then I would take one pass, one take and just play whatever I felt."

That freewheeling, "if it sounds good, use it" attitude that helped Glasper add sonic layers to TPAB also benefitted Knxwledge, whose previously unheralded "So[rt]" beat became the instrumental for K. Dot's TPAB standout, "Momma." "It’s one of those ones where like, if you see it, you’re going to be intrigued because the title is so crazy, the cover is so crazy and it’s five years ago now so like, if you see all the features and like… I would be intrigued if I was a new person just trying to get into music, listening to old stuff," Knxwledge tells XXL. "2015 was special."

Working with Kendrick Lamar, whether it was in the studio or through a phone call or a text message, the folks behind some of the album's most important songs knew they were a part of something that would last. Today, to honor the album's fifth anniversary, XXL reveals 10 untold stories from Rapsody, Robert Glasper, Rahki and Knxwledge as they discuss their contributions and reactions to the legendary LP.