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.

In his pomp there was no genre or story this director couldn’t turn to gold – despite never being nominated for an Oscar

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Consumption today is driven by the algorithm: “If you liked that, you’ll love this …” But Rob Reiner was a film-maker who beat the algorithm in the days before there was even one to beat. He was impossible to predict, at least during his golden years. How could one man make the most inspired mockumentary of all time, a handful of zinging romcoms, a coming-of-age yarn, a knowing fairytale comedy, a gruesome yet screamingly camp thriller and a hokey-but-fun courtroom drama? Well, he did – and all in the first decade of his directing career.

US audiences loved him first as an actor: he was the liberal son-in-law known as Meathead in nearly 200 episodes of the late-1970s sitcom All in the Family, based on the UK favourite Till Death Us Do Part. He remained in front of the camera for his 1984 directorial debut This Is Spinal Tap, which chronicled an entire band of meatheads. In fact, his face is the very first thing we see: he plays the ingratiating documentary-maker Marty DiBergi, an affectionate parody of Martin Scorsese as glimpsed in the off-stage scenes of The Last Waltz, his concert film about the Band. Spinal Tap’s chief target, though, was the speed with which fame can turn you dumb – or make idiots believe themselves to be geniuses. The heavy metal band, played by Michael McKean, Christopher Guest and Harry Shearer, put it best: “It’s such a fine line between stupid and clever.”