Ryuichi Sakamoto: Coda is a documentary as composed and improvisational as its subject. A film five years in the making, it follows the Oscar-winning composer and activist as he visits the Fukushima nuclear reactor following the devastating 2011 earthquake and tsunami, then through his 2014 diagnosis with stage three throat cancer, which initially left the direction of the documentary in uncertainty.

But Sakamoto responds to the various crises in his life with a swift matter-of-factness — this is just how things must be done. His bout with cancer was the longest he had ever gone without making music; just over a year after his diagnosis, he returned to work, this time on the score for Alejandro Iñárritu’s The Revenant. His approach, director Stephen Nomura Schible said, was a major influence on the film.

“Ultimately, Ryuichi’s composing process became our guide and brought us to the unique form that the film organically acquired,” he recalled. “I wanted this film to explore how Ryuichi’s awareness of crises had developed and how it has brought change to his musical expression.”

At the Q&A following Coda’s Tribeca Film Festival premiere, Sakamoto sat down with Schible to discuss everything from a meeting with the late Studio Ghibli co-founder Isao Takahata (“He fired me. My music was too serious for his films”), to being featured on the soundtrack for Call Me By Your Name by director Luca Guadagnino, whom he now considers a friend (“He uses music very carefully, with a lot of respect”).

Schible spoke of the unexpected surprises of working with Sakamoto, who thrives on improvisation: “Whenever I would have a plan, he would utterly destroy everything I tried to do. I was completely taken apart.”

“He tried to match his film to my music, but I always try to match my music to films,” Sakamoto explained, laughing. “This has happened for the first time in my life.”

This sort of spontaneous fluidity is what has driven most of the composer’s work throughout his decades-long career. In the film, we see his restless creative energy at work, as he edits and adds to tracks while sitting on an exercise ball in his home studio. He improvises on a track playing in the background by running a violin bow across a hi-hat cymbal to unnerving effect. He listens to his environment with a playful curiosity, endlessly experimenting with whatever he can find.

Woven throughout the documentary are scenes from the films he has scored, as well as footage from his live performances. We see much younger versions of him act alongside David Bowie in Merry Christmas, Mr. Lawrence, and perform as part of the hugely influential Japanese techno-pop band Yellow Magic Orchestra. Among these nostalgic clips is an interview from his 1985 documentary Tokyo Melody, in which he muses on what he finds interesting in a rapidly changing Japan: “I’m concerned by a deficient technology. In other words, errors or noises. It absorbs me and I wonder if new cultural currents could emerge from this deficiency.”

As we listen to observations from his past self, it becomes clear this is an artist who has spent his career chasing his interests relentlessly, a passion that has allowed him to evolve with his changing surroundings. Playing a sustained note on the piano, he waits for the sound to fade out into the background: “I’m fascinated by the notion of a perpetual sound. One that won’t dissipate over time.” Death and disaster are running themes in Coda, but Sakamoto’s musical responses to these crises will be his legacy.

One of the film’s best lines also comes from the site of another kind of disaster: the melting glaciers in Antarctica. Crouched next to a hole in the ice, Sakamoto lowers a mic into the water to capture the trickling sound of melting ice, which he’ll later edit into one of his tracks. “I’m fishing for sound,” he jokes.

Ryuichi Sakamoto: Coda will be released July 6th, 2018.