Michael McKean Admits Making “This Is Spinal Tap” 40 Years Ago Was 'a Long Chore' (Exclusive)

The actor will is reprise his role as a fictional rockstar in the upcoming sequel of the 1984 cult classic

Though now considered a cult classic, it turns out that This Is Spinal Tap was not an easy movie to make.

The 1984 favorite, which stars Christopher Guest, Michael McKean, Harry Shearer and Rob Reiner, helped popularize the "mockumentary" film genre and tells the story of the fictional band Spinal Tap as they’re being documented by a filmmaker. Now, 40 years after the film first hit theaters, McKean, who plays David St. Hubbins, remembers the trials and tribulations the cast and crew went through to get it made.

“It was such a struggle to get it done,” he told PEOPLE at the season 2 premiere of The Diplomat in New York City, noting that “there weren't a lot of features like it at the time.”

“What we had was 20 hours of film and we got it down to 85 minutes. It was a long, long chore,” the 77-year-old continued. “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.”

And keep it alive they did. In 2022, it was announced that a sequel to the film, Spinal Tap II, would be made, starring much of the original cast, including Fran Drescher.

Related: This Is Spinal Tap Director Says Sequel Will Feature Paul McCartney, Elton John and a 'Few Other Surprises'

“If you think those guys were sad when they were young ...” McKean teased of what to expect in the sequel, slated to be released next spring. “It's tragic in the funniest way — hopefully.”

In the years since the film’s premiere, McKean has had an expansive career in film and TV with roles on Saturday Night Live and Better Call Saul, and in 2004 was nominated for Best Original Song at the Oscars for a song he wrote with his wife Annette O’Toole. More recently he stars as President William Rayburn on The Diplomat.

Related: Fran Drescher Confirms She Will Be Reprising Her Role in Upcoming This Is Spinal Tap Sequel: 'Get Ready'

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“I love the show,” McKean shared of the Keri Russell- and Rufus Sewell-led political drama, which is now streaming its second season on Netflix.