Spoof documentaries once skewered subjects by dialling comic ingenuity up to 11, but the genre has stagnated – replaced by showbiz puff pieces and right-wing provocations. Has their time passed?

In the satirical mockumentary The Moment, Charli xcx fears (and eventually embraces) the death of Brat summer, the cultural sensation that made her sixth album a phenomenon. But the film – which stars the singer as a fictionalised version of herself – strains to land jokes out of Charli’s identity crisis and lacks the giddily intoxicating rush of that 2024 album. Watching The Moment shortly after its lukewarm reception at Sundance, I sensed something dying, but it wasn’t Brat – it was the mockumentary style itself.

How did mockumentaries grow so … tiresome? Once a novel narrative format brilliantly deployed by directors such as Christopher Guest and the late Rob Reiner, the mockumentary now feels nearly as stale as the formulaic films it aims to lampoon. It’s a sad state of affairs. For much of the last half-century, faux-documentary film-making flourished under the perverse minds of countless comedy greats, from Monty Python’s Eric Idle, who lampooned Beatlemania with 1978’s wackily irreverent mock-doc The Rutles: All You Need Is Cash, to Albert Brooks, who made his directorial debut with 1979’s proto-reality television spoof Real Life.

Reiner’s own films reshaped modern comedy and drama with their intelligence, empathy and range. But through his company, Castle Rock, he paved the way for Seinfeld, Sorkin and many more

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As a film-maker, Rob Reiner championed humour, civility and intelligence – qualities you suppose would be out of step with the Hollywood of the 1980s where he made his name, and in the 1990s where he scored a series of extraordinary, far-reaching successes. Reiner had a family interest in the workings of on-screen comedy: his father Carl had played a key role on Sid Caesar’s TV shows, which themselves were revolutionary, and helped birth a new generation of screen comics by directing Steve Martin’s film debut The Jerk. Rob had become a household name as Meathead, the liberal foil to Carroll O’Connor’s bigoted Archie Bunker in 70s sitcom All in the Family (the equivalent to Mike Rawlins v Warren Mitchell in the British original, Till Death Us Do Part). But it was as a director and producer that he really made his impact felt.

In 1984, Reiner released This Is Spinal Tap, a “mockumentary” about a fictitious heavy metal band from the UK that rewrote the rules on what comedy could do. It sent up rock’n’roll behaviour and codified its cliches (with Reiner himself doing a hilarious parody of Martin Scorsese’s hosting role in The Last Waltz) and gave us zingers that haven’t lost their comedy power more than 30 years on: “The numbers all go to 11”, “it’s such a fine line between stupid, and er … clever.” Its deployment of improvised comedy was revolutionary for a Hollywood feature, and while Reiner wasn’t the first to use the fake-documentary techniques for comedic purposes (that goes back at least to Woody Allen’s Take the Money and Run), it hugely popularised the mockumentary style; subsequent efforts include Bob Roberts, Fear of a Black Hat, Drop Dead Gorgeous and Borat: Cultural Learnings of America for Make Benefit Glorious Nation of Kazakhstan. All these owe Tap a huge debt – as well as the microgenre of star Christopher Guest’s improv-mockumentaries: Waiting for Guffman, Best in Show and A Mighty Wind. Almost incidentally, Spinal Tap became a sort-of-real band, with tours, record releases and a follow-up feature (Spinal Tap II: The End Continues), in which the presence of music industry titans Paul McCartney and Elton John demonstrated the high regard in which the original was held.