The pantheon of rock legends brims with iconic names. Jimmy Page. Jim Morrison. Joan Jett. And who can forget those deafening British metal mavens Nigel Tufnel, David St. Hubbins and Derek Smalls of Spinal Tap.

In 1984, director Marty DiBergi (Rob Reiner) brought us into the band's tunefully dysfunctional world with the documentary "This Is Spinal Tap." Now, four decades later, DiBergi is back with "Spinal Tap II: The End Continues" (in theaters Sept. 12), which chronicles the band's one-off final gig after not seeing each other in 15 years.

In a twist, two other music legends appear in the new film: Elton John, who joins the band for a performance of their big hit "Stonehenge," and Paul McCartney, who humbly tries to settle a debate over a key change in a St. Hubbins song, which earns the Beatle glares from the long-haired rocker.

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USA TODAY recently caught up with Tufnel (Christopher Guest), St. Hubbins (Michael McKean) and Smalls (Harry Shearer) − in character − to discuss their return to the spotlight after becoming comfortably ensconced in their new lives as a cheesemonger (Tufnel), home recording studio tinkerer (St. Hubbins) and glue museum proprietor (Smalls).