Paul Simon Faced Unexpected Struggles. Cameras Were Rolling.

“That was a lovely moment that Andy intuited and put together,” Gibney said. “The contrast between that love and then the bitterness laid over that sweet moment captured in a poetic way the ebb and flow of time and memory, happiness and sadness, all rolled into one.”

According to Simon, the inspiration for “Seven Psalms” came to him in a dream in 2019. Gibney filmed him as he rehearsed and recorded the album in Wimberley, Austin, Houston and New York, directed singers and instrumentalists, and sang alongside his wife, the musician Edie Brickell.

The filmmakers also pored through hundreds of hours of audiotapes and archival footage and thousands of photos, many from Simon’s own collection. Simon lived much of his life in front of the camera, so it was less a matter of finding, say, footage of him singing “Cecilia,” than it was of choosing which version out of dozens of them was the best.

The movie offers a wealth of interesting trivia, such as how the actor Charles Grodin directed the documentary “Simon and Garfunkel: Songs of America” in 1969, and then appeared as a Garfunkel impersonator, complete with a wig, alongside Simon in a “Saturday Night Live” skit. Or how the organizers of the 1967 Monterey Pop Festival expected Simon and Garfunkel, as well as fellow acts Jimi Hendrix and Janis Joplin, to “perform without fee.”

As for the songs, there are many, and many of them played at length (the entirety of “American Tune”; Aretha Franklin’s powerful 1971 cover of “Bridge Over Troubled Water”). Simon’s discography is so extensive and hit-filled that “Kodachrome” — “Kodachrome”! — doesn’t even make an appearance. “It’s already a three-and-half-hour movie,” Grieve said. “If we put in every amazing song, you’d have a 10-part series.”

For Gibney, who has made many films over the years about villains and cheats, corruption and deception, being able to tell the story of such a beloved songwriter was a welcome change. “I love his music, so this was a labor of love in the truest sense,” he said.