‘In Restless Dreams: The Music of Paul Simon’ will leave you feeling groovy

As much about the singer-songwriter’s life now as then, “In Restless Dreams: The Music of Paul Simon” is an unabashed celebration of musical genius that’s at its best when looking back. Spanning 3 ½ hours, director Alex Gibney spends a bit too much time on Simon today, but it’s still a fitting tribute to a talent who, to quote his song, went looking for America, and had America and indeed the world find him in return.

As much about the singer-songwriter’s life now as then, “In Restless Dreams: The Music of Paul Simon” is an unabashed celebration of musical genius that’s at its best when looking back. Spanning 3 ½ hours, director Alex Gibney spends a bit too much time on Simon today, but it’s still a fitting tribute to a talent who, to quote his song, went looking for America, and had America and indeed the world find him in return. “Verse one,” as it’s labeled, of this two-part MGM+ presentation features Simon working on his 20th and final album, “Seven Psalms,” dealing with the frustration of hearing loss and the toll exacted on his frail-sounding voice as he quietly lives in Texas with his wife, singer Edie Brickell. (Simon met both Brickell and previous wife Carrie Fisher on “Saturday Night Live,” and producer Lorne Michaels is among the luminaries sharing memories.) Along the way, Gibney (adding to a musical filmography that includes biographies of Frank Sinatra and James Brown) goes back to Simon’s upbringing in Queens, New York, the formation of his partnership with childhood friend Art Garfunkel, and the belated breakthrough they achieved with “The Sound of Silence,” which, followed by their music’s use in director Mike Nichols’ “The Graduate,” vaulted them into the musical stratosphere. “I said to myself, ‘My life is irrevocably changed,’” Simon recalls, having attended (and hated) law school for a time before eventually dropping out. Despite extraordinary success, Simon describes what became “an uneven partnership,” with Simon writing the songs while Garfunkel went off to pursue an acting career (beginning with a role in Nichols’ “Catch-22”), placing stress on their relationship. Those tensions came to a head while producing “Bridge Over Troubled Water,” a vocal showcase for Garfunkel. Notably, Simon & Garfunkel (who, as an amusing footnote, originally went by the label-given name Tom & Jerry) couldn’t repair the fracture despite the appetite for them to do so after their historic reunion concert in Central Park, which attracted an estimated 750,000 people.