The language of American comedy would have been a lot less sparky without Buck Henry, who has died aged 89. He helped shape one of the most revolutionary films of the 1960s (The Graduate), co-wrote one of the funniest of all time (What’s Up, Doc?) and scripted the movie that became the springboard for Nicole Kidman’s career (To Die For). Each new wave of comic talent took it in turn to pay tribute to Henry in some way; Tina Fey, who cast him as her character Liz Lemon’s badly behaved father in 30 Rock, was only the most recent.

Henry was the fourth writer to try to adapt Charles Webb’s 1963 novella The Graduate, about an aimless young man who drifts into an affair with an older married woman, and he was instrumental in making drastic tonal and narrative changes that transformed the main character from a self-righteous homophobe to a plaintive and over-earnest young twit who is confounded by adult hypocrisy, his own impossibly high standards and the nebulousness of his privileged west coast surroundings. Henry, whose previous experience had included co-creating the hit TV spy spoof Get Smart and appearing on chat shows posing as a campaigner fighting to keep animals clothed (“A nude horse is a rude horse”), was brought on to The Graduate by the director, Mike Nichols, himself an accomplished comic improviser from his double-act with Elaine May. Working together, they created comic dynamite from the generational rupture between the youth of the 1960s and their Eisenhower-era parents, and found their ideal lead in the gawky newcomer Dustin Hoffman.

Hopes for the movie were modest. Henry recalled: “Who did it star? Anne Bancroft, [who] wasn’t a money actress, and this kid with the big nose.” But the film became a phenomenon as well as a success. In January 1968, a month after it opened, Henry walked into a New York cinema to find the sold-out audience hollering the dialogue at the screen. “It was bizarre to sit there and hear 500 or 600 people saying ‘plastics’ all at once.” The only downside was that a previous writer on the project, Calder Willingham, had successfully lobbied for a co-writing credit. Though as the producer Lawrence Turman said: “Everyone knew Buck wrote the script.” Henry’s next collaboration with Nichols, a berserk film of Joseph Heller’s Catch-22, continued the mood of comic despair and dislocation but failed to make the same cultural impact.

Most screenwriters are unseen if not unsung but Henry was unusual in being constantly visible: long after his stint as the president of the Society for Indecency to Naked Animals, he was industrious in front of the camera as well as behind the typewriter. He was an accomplished actor, providing the connection between any number of disparate figures in the Venn diagram of 20th-century cinema: he was the attorney in bottle-glass specs who goes into business with an alien played by David Bowie in Nicolas Roeg’s The Man Who Fell to Earth, the mob accountant murdered at the start of John Cassavetes’ Gloria and, best of all, a middle-class Manhattan parent who cuts loose and samples the counterculture in Milos Forman’s playful 1971 comedy Taking Off. Henry also turns up as himself in the long, single-take opening of Robert Altman’s The Player, where he is seen shamelessly pitching a sequel to The Graduate: “Mrs Robinson has had a stroke, so she can’t talk…”

His career was not short of highlights but the 1972 delirious screwball comedy What’s Up, Doc?, which he wrote after the director Peter Bogdanovich was reportedly unhappy with the original draft by the Bonnie and Clyde writers Robert Benton and David Newman, was one of which he was rightly proud.

“What’s Up, Doc? makes me totally happy in a way that the other films I’ve written don’t, because Bogdanovich was so good at doing that tone,” Henry said. “I have no qualms about any sequence in it. They all seem to me to work on their own level. It’s a very cartoony, superficial level, but it’s at also very complicated technically. And it’s interesting to see it work out. It’s great fun. It’s very hard to do but it’s great fun to do. And when it works it’s kind of a revelation.”