Brett Morgen’s intro at South by Southwest for his new film, Kurt Cobain: Montage of Heck, was one of the shortest I’ve ever witnessed.

While some directors ramble about their gratitude towards the festival, or rattle off a long list of thank-yous before their movie plays, Morgen took the stage and simply said, “I know how long some of you have been waiting to see this movie, so let’s just roll it”.

He couldn’t have been more right. The mystique and fascination surrounding Nirvana’s notoriously troubled frontman Kurt Cobain has only strengthened over the last 21 years since his death. Many of us assumed we’d finally heard all there is to hear about the late musician, but Morgen’s feature documentary uses never-before-seen home movies, paintings, demos, video dailies and interviews with Cobain’s closest family and friends (some of whom have never even done an interview until now), as well as animated sequences to offer an unprecedented look through the rocker’s eyes. Montage of Heck is the intimate, definitive look at Kurt Cobain’s life that fans have waited decades for.

Morgen (known for The Kid Stays in the Picture, Crossfire Hurricane and the Oscar-nominated On the Ropes) was with the project for years before it finally began to take shape. MovieMaker spoke to the documentarian at SXSW this March to discuss how he approached both the film’s talking-head interviews and animated sequences, his strategy for slogging through footage, and the importance of sound design in this multi-faceted music documentary.

Andy Young, MovieMaker Magazine (MM): This is billed as the first authorized Kurt Cobain documentary. What took so long?

Brett Morgen (BM): I think Frances [Bean Cobain, Kurt’s daughter and executive producer of the film] needed to come of age. Since Kurt died there was obviously a great deal of tension over the last 20 years between Courtney [Love], Krist [Novoselic] and Dave [Grohl], and that alone made it impossible for there to be a proper movie. But after Frances emancipated herself and gained a stronger foothold in the business, the gentleman who was appointed the estate manager helped us push things forward. And when I reached out for interviews and mentioned Frances’ involvement, that’s when people like Wendy [Kurt’s mother], Don [Kurt’s father], Kim [Kurt’s sister], Krist and Dave came on board. There’s a trust and responsibility that comes with that.

MM: You have Kurt’s art and home movies, but you also found things like dallies from Nirvana’s music videos—which I didn’t even think still existed. So where was all this footage sitting?

BM: I called Sam Bayer [director of the “Smells Like Teen Spirit” music video], and he thought they didn’t exist anymore either. I think we got them from Universal. I got “Come as You Are” from director Kevin Kerslake, and we found the 35mm negative for “Heart-Shaped Box” and re-transferred it. All the audio archives came from Kurt’s storage. Wendy saved everything; she had those home movies and all of Kurt’s art. And then we had great support from the Nirvana fan community giving us access to their material. I feel like we got everything that’s out there.

MM: The doc uses both what the public hasn’t seen before and well-documented Nirvana material. As one of the film’s editors, how did you organize and mark all this footage?

BM: It difficult with the audio because it’s hard to keep track of 200-plus hours of content with no visual benchmarks. But the video was more manageable than you think; there was about five hours worth of Kurt up to the age of eight, maybe 20-plus hours from ’91 on. All the interviews and animation were manufactured by us and that’s half the film right there. I mean we had 1,000 hours of footage, but a lot of that is concert footage that was used on a need-be basis.

A shot from Kurt Cobain: Montage of Heck

An archival still of Kurt Cobain and daughter Francis Bean Cobain

MM: You use several narrative devices in this film (interviews, animated sequences, archive footage).At what point during the film are you deciding to use these?

BM: Normally I go into a movie with a pretty good idea of what the look and arc is. This one was a little different. All my films are an attempt to create an experience of the subject rather than a history, so they adapt their personality in the presentation. A film on Kurt Cobain is going to be different from a film on producer Robert Evans [subject of The Kid Stays in the Picture], because Kurt and Rob are different. So knowing it was about Kurt, I knew it needed to have an analog, rough-around-the-edges feel.

The film was intended to be Kurt’s interior journey through life, and his art would give us access to that journey. I was going to only use his interviews but I found myself drifting. He’s so expressive in his work, but the one area he was lacking in was his interview voice. It wasn’t an accurate representation [of himself], so at that point I knew I had to reach out to those closest to him to contextualize. There’s a formalism in the way these talking heads are constructed that make it feel almost outside the film, because we’re stepping out of Kurt’s immersive subjective experience. Because I’ve never done talking-head interviews in my other films, I was excited by the challenge. You have a limited means to talk to the viewer in montage, color grading and sound design, and you need to exploit them.

MM: Your talking-head interviews are very cinematic in that you have several different camera angles, and the lighting changes from morning to night throughout the film. How did you approach shooting that?

BM: I wanted the interviews to feel as if we spent a very long day talking about Kurt. What made it manageable was that, when I do interviews, I like to do them in order. So we wanted “morning in America” light to be early Kurt, and as the journey went on, we’d have to adjust for lighting. What became challenging was some people would go off on tangents, like talking about heroin, in our morning light, and I’d have to stop them. It required a certain degree of restraint to make sure someone didn’t say something great in the wrong lighting.

MM: How did you go about writing your questions to construct a narrative?

BM: The thing about this film is people can only talk about what they experienced. You can really only have Don talk about Kurt’s early life, because the rest is all hearsay to him. So I knew which part of Kurt’s story each character would inhabit, which helped focus the questions. My approach to doing interviews is by the time I’m doing them, I’m well-versed in the subject. I’ll write them out the night before but won’t have to look at the footage until the interview is over, so I can make sure I got everything.

MM: You use two different types of animation when bringing Kurt’s audio and journals to life. How did you figure out which sections were going to be animated, and how did you direct those sequences?

BM: There were two different animators: the after-effects by Stefan Nadelman on Kurt’s journals and drawings, and then Hisko Hulsing’s animated sequences.

With Hisko, I reached out to him after I cut the audio and scripted out the action for the scenes that he was animating. There was a long back-and-forth with the storyboards. Once they were locked, Hisko put together a team of animators to draw 6,000 individual frames, while he set about painting the 58 backgrounds.

Stefan was tasked to bringing Kurt’s journals and drawings to life. We’d use a still holding shot in the timeline, and then we started experimenting with the right visual approach to his journals. There was a tremendous amount of back-and-forth with Stefan, trying to design the right look for the film. As Stefan works alone in a digital realm, retakes were not an issue, so we went through dozens of revisions with each shot before we arrived at the final look. We wanted it to look like Kurt shot the journals himself with a Super 8 camera. You can’t farm that stuff out. As a director, those pages are like your set. I view photo animation as an endless world of possibilities. To me, it’s akin to walking onto a soundstage where we discover a set—but the set hasn’t been lit and the camera hasn’t been placed. How we light it and frame it can and will shape the audience’s experiences with that moment.

Documentarian Brett Morgen

Documentarian Brett Morgen. Photograph by John Fleenor

MM: In terms of crafting the sound design, and what I’ll call the score—because you use so many different variations of Nirvana songs—how do you go about building the audio of a film that relies so heavily on its sound?

BM: When I went through Kurt’s possessions, I thought the video or art would be our biggest asset. But I found the audio to be a direct portal into Kurt. It was absolutely unfiltered and captured his personality better than any other medium, whether he was recording demos or goofing off with a microphone with the “Montage of Heck” mixtape. So we collected all his audio, screened it and pulled pieces we’d use as building blocks in the film.

There’s two types of sound design in the film: There’s Kurt’s material as sound design that we’ve repurposed, hearing the world the way Kurt heard it. And then there’s the sound team—Steve Peterson and Cameron Frankley—who initially were using their own sound effects like they would on a Hollywood movie. Composer Jeff Danna started adding the “Jeff Danna” twist to Nirvana arrangements. Even in the orchestral arrangements, we tried to use instrumentation that Kurt actually used in his music so we could get that grammar and that language. So we all had to approach the film differently than we normally would another film. We had to approach it through Kurt’s lens so it felt organic and cohesive within the fabric we were presenting. MM

Kurt Cobain: Montage of Heck opens in limited theaters April 24, 2015 and will premiere on HBO May 4, 2015, courtesy of HBO Documentary Films.