Carole King, James Taylor, and Danny Kortchmar in Immediate Family (Magnolia Pictures)

Director Denny Tedesco’s enjoyable—and, for a certain segment of its audience, nostalgic—documentary follows the long and winding careers of four men who are widely considered among the best session musicians of the rock era: drummer Russ Kunkel, bassist Leland Sklar, and guitarists Danny Kortchmar and Waddy Wachtel. They, along with another session player, Steve Postell, formed the group Immediate Family, described by one talking head as “the best cover band alive” since they perform songs the quartet originally recorded with a veritable who’s-who of rock stars throughout the 1970s and ’80s.

Tedesco sits down with the musicians, who reminisce and trade war stories about their musical exploits, spinning endlessly entertaining yarns about their many topnotch collaborations with James Taylor, Jackson Browne, Linda Ronstadt, Stevie Nicks, Warren Zevon, Don Henley, and so many others. It was pretty much an accident that they started playing together, as Kortchmar (nicknamed “Kootch” by pretty much everybody) became friends with Taylor when they were both teenagers, bonding over their shared love of music while vacationing with their families on Martha’s Vineyard.

After Taylor’s recording career began—he was signed to the Beatles’ Apple Records, but his debut album flopped—producer Peter Asher brought in Kootch, Kunkel, and Sklar. They became Taylor’s backing band in the studio and on tour for several years. Kootch and Kunkel also played on Carole King’s classic Tapestry album, with King still marveling at Kootch’s inspired guitar solo on the hit song “It’s Too Late.” Possibly the trio’s most notable contributions came in 1977, when they went on the road with Jackson Browne, who recorded his best-selling album Running on Empty live. They provided the musical muscle to his most popular tunes.

Although Sklar was a classically trained pianist who turned to playing bass, the others got the rock ’n’ roll bug early—the Beatles’ appearance on Ed Sullivan seems to have been a point of entry for each—and formed bands that didn’t go anywhere. Wachtel’s journey began when he played on early records of Zevon and Ronstadt. Tedesco’s interviews with several of these artists provide anecdotes that are revealing and often funny and heartfelt. (Zevon, who would almost certainly have been endlessly quotable, sadly died in 2003.)

Henley admits that, after the Eagles disbanded in 1980, he didn’t think he could be a successful solo artist, but after starting to work with Kootch, their collaborations made Henley a huge star in the ’80s with hits like “Dirty Laundry” and “All She Wants to Do Is Dance.” Phil Collins named Sklar as the man whose innovative style of bass playing directly influenced some of Collins’s biggest hits, including “Don’t Lose My Number” and “Take Me Home.” And Keith Richards, when he did some solo work away from the Rolling Stones in the ’80s, agreed with drummer Steve Jordan (musical director of Richards’s band, the X-Pensive Winos) that Wachtel was their first choice to join them due to his innate musicality and ability to always play the perfect note. Other stories about these players’ collaborations on classic rock songs are legion.

As an actual group, the Immediate Family today perform their own new rock songs, and even though they are quite solid, it’s their work with Taylor, Browne, Ronstadt, Henley, and others that has earned them the eternal admiration of generations of rock fans.