Michael McKean teases “This Is Spinal Tap” sequel will be 'tragic in the funniest way'

"If you think those guys were sad when they were young…"

The upcoming sequel to This Is Spinal Tap will be turning the pathetic knobs all the way to 11.

Michael McKean talked up the long-gestating movie in a recent interview with PEOPLE, teasing, "If you think those guys were sad when they were young…" The Better Call Saul actor added, "It's tragic in the funniest way — hopefully."

The sequel to the 1984 rock mockumentary will see McKean reprise his role as David St. Hubbins, the frontman the fictional metal band. Christopher Guest and Harry Shearer will also return as guitarist Nigel Tufnel and Derek Smalls. Rob Reiner, who made his directorial debut with the original movie, is helming the sequel, and also reprising his role as documentarian Marty DiBergi.

Related: Spinal Tap's Derek Smalls is mad as hell at Barbie on new song 'Must Crush Barbie'

The original Spinal Tap, which helped popularize the mockumentary genre, was almost entirely improvised by the cast — and McKean said it wasn't an easy process. "It was such a struggle to get it done," he told PEOPLE, adding that "there weren't a lot of features like it at the time."

The film famously shot far more material than it ended up using in the final cut. "What we had was 20 hours of film and we got it down to 85 minutes. It was a long, long chore," McKean recalled. "But once we started showing it to people and knowing that the audiences who were there for the film really dug it — it was never going to be Ghostbusters, Ghostbusters was that year. It wasn't going to be Splash, it wasn't going to be one of the big, big money comedies — but we also knew that the people who liked it would like it very much and would keep it alive."

Related: Eugene Levy says you'll be Waiting for Nothin' if you want another Christopher Guest collaboration

The actors reunited as the fictional band for two follow-up albums, 1992's Break Like the Wind and 2009's Back from the Dead. The former album received a made-for-TV mockumentary that primarily consisted of concert footage, while the latter had an hourlong in-character interview released on DVD.

"When it was announced that Spinal Tap would reunite for one final concert, Marty DiBergi saw this as a chance to make things right with the band who viewed This Is Spinal Tap as a hatchet job," Reiner said in a statement when the new film was announced. "So he left his position as visiting adjunct teacher's assistant at the Ed Wood School of Cinematic Arts in pursuit of film history."

Related: Rob Reiner says Martin Scorsese was 'mad' about Marty DiBergi character in This is Spinal Tap

Last year, Reiner revealed that the sequel will feature appearances from a number of A-list musicians. "Paul McCartney is joining us, and Elton John, and a few other surprises. Garth Brooks," he said.

The film was originally slated to release in March 2024 but delayed due to the writers' and actors' strikes in 2023. In his most recent update, Reiner said the film was aiming to release in "late spring or early summer" of 2025.

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