The anticipation for Marvel’s Black Panther flick is getting stronger and stronger each day. But perhaps equally anticipated is the film’s soundtrack produced Kendrick Lamar and his label Top Dawg Entertainment.

In the days leading up to the release of Black Panther: The Album, director Ryan Coogler spoke to NPR about the project and how the TDE crew eventually became involved. He revealed that the initial plan was for Kendrick to contribute only a few songs to the film; however, the rapper’s role became much greater after he was given an extended look at the movie.

“I've been a massive Kendrick fan ever since I first heard him, since his mixtapes, and I've been trying to track him down,” Coogler said. “Eventually I caught up with him a couple years ago—first with Anthony 'Top Dawg' Tiffith, who runs his label, and then later on sat down with him and Kendrick and just spoke about much his music affected me. He talked about my movies that he had seen, and we said if the opportunity comes, we'd love to work with each other on something.”

Shortly after K-Dot completed his fourth studio album Damn, Coogler reached out to the rapper to discuss his involvement.

“To Marvel's credit, they really supported the idea of getting some songs from him,” the director explained. “At first, he was just going to do a few songs for the film, and then he came in and watched quite a bit of the movie, and the next thing I know, they were booking a studio and they were going at it.”

TDE producer Sounwave told NPR that the team had started working on the album during Kendrick’s Damn Tour last summer, and that about half of the soundtrack’s concepts were developed while on the road.

“[During] The Damn Tour, we probably came up with 50 percent of it — the production, the hooks and ideas,” he said. “When we got back from the tour in September, that's when we were able to execute our ideas and reach out to people we respect and whatnot ... kind of just put the stamp on it. So, I want to say those two months was the most vital on that tour, in terms of creative process.”

Black Panther: The Album includes appearances by everyone from SZA and the Weeknd to James Blake and Travis Scott to Vince Staples and Jorja Smith. The film’s score was helmed by Coogler’s previous collaborator Ludwig Göransson, who is best known for his work with Childish Gambino. This fact made many fans wonder: Why wasn’t Childish included on the soundtrack?

Though the "Redbone" artist didn’t receive a credit on Black Panther: The Album, it turns out he did contribute to the film’s sound. Rolling Stone’s film critic Peter Travers pointed this out in his recent review, in which he applauded the composer’s work as well as the various hip-hop artists who assisted him.

“[…] It's fair to mention Ludwig Goransson's rousing score with hip-hop song contributions from the likes of Kendrick Lamar, Sam Dew, Vince Staples and Childish Gambino,” he wrote.

We’ll have to wait and see just how big Childish’s contribution was.

As we wait for the album to drop, you can check out some its previously released singles here. Black Panther: The Album is set to release this Friday (Feb. 9), one week before the film hits U.S. theaters.