When it began, cinema boasted of having left the fuddy-duddy art of literature behind. Silent films dispensed with language and let bodies do the talking; later, the director Luis Buñuel declared himself to be ‘agraphic’, allergic to writing. Non-Fiction, nimbly written and a little staidly directed by Olivier Assayas, catches up with the debate between words and images at an interesting moment. Today cinema is threatened with the same obsolescence to which it believed it had consigned the printed book; the film’s characters oscillate between old and new cultures – the verbal and the visual, the analogue and the digital – with a dualism to which the film’s French title, Doubles Vies, draws apt attention.

Alain (Guillaume Canet) is a publisher with a venerable literary backlist who risks losing his firm to a crass media mogul. His wife, Selena (Juliette Binoche), salves her conscience by quitting a lucrative television show in which she plays a cop so she can return to classical theatre in Racine’s Phèdre. Léonard (Vincent Macaigne), one of Alain’s authors, is proudly unpopular: his novels, he says with a wry lapse into English, are ‘worstsellers’. Léonard’s wife, Valérie (Nora Hamzawi), subsidises his old-fashioned endeavours by working as an image consultant for a politician.

This being a French film, the first three – when not editorialising about their professional woes or stepping outdoors for a cigarette – are busy cheating on their spouses. Valérie has no time for liaisons: she needs to manage press coverage of her boss, who has been arrested with a prostitute in the Bois de Boulogne. Why, she wonders, can’t he be more duplicitous, something politicians usually excel at? The other philanderers stay within their own closed circle. Selena and Léonard have a discreet arrangement, whereas Alain’s illicit relationship is with his colleague Laure (Christa Théret), whom he hires to take charge of his firm’s digital initiatives.

Laure is the representative of an amnesiac new generation. She welcomes a future in which print will dematerialise and is shockingly indifferent to the cinematic canon: with a Gallic shrug, she admits to never having seen any of Ingmar Bergman’s films (although, somewhat implausibly, she does quote a line from Visconti’s The Leopard). She also has tattoos, and a female lover on the side. We are invited to regard her as a post-human creature: a person, she explains to the aghast Alain, is a function of the algorithms that define his or her habits as a consumer. The film ends with Jonathan Richman and The Modern Lovers singing ‘Here Come the Martian Martians’. I assume that Laure – who by then has disappeared, having taken a pan-European marketing job – is in the vanguard of the extraterrestrial army.

Books furnish the rooms of these people and seem to matter more than their stray human appendages. Alain and Selena have a young son, and they occasionally wonder – as do we, having seen him just twice – where he is. Valérie becomes pregnant, which leaves Léonard puzzling over the precise location of the lentil-sized foetus (he probably thinks of those remaindered novels as his authentic offspring). ‘I believe in the implicit,’ says Valérie, who would rather not know about her husband’s flings. Selena keeps the faith with language and literature by being explicit, and insists on verbalising the end of the affair with Léonard. ‘We have put it into words,’ she says after ditching him in a cafe.

Adultery matters less here than cultural adulteration. The characters casually deride the popular novelist Nora Roberts and the franchised movie series The Fast and the Furious; they deplore the decline of newspaper sales, the binge-watching of television box sets and the proliferation of gossipy book programmes on the radio. Of course all of us agree – but isn’t this precisely the sort of thing Assayas is attacking in an exchange about the way Twitter and Facebook isolate people in ‘a fictional world ruled by their prejudices’?

One scene does contain a sharp jibe about this sort of cultural snobbery. Selena apparently treated Léonard to a blowjob during Star Wars: The Force Awakens, though when he fictionalises the incident in one of his novels, he changes the film to Michael Haneke’s The White Ribbon, a dour parable about the psychological origins of the Third Reich. Another in-joke is more self-congratulatory. Alain, wanting to sex up his output, tries to recruit stars to record audiobooks. He reports that Juliette Binoche has been approached, but hasn’t replied. Léonard suggests that Selena might share her famous colleague’s email address with Alain. That, says Selena, would be improper, but as a favour she offers to impart the name of Binoche’s agent. Is Binoche – who walks through the role of Selena, which is a day off in comparison with the more fraught character Assayas created for her in Clouds of Sils Maria – being asked to mock her own stardom or to smile knowingly as her mystique is reinforced?

In Personal Shopper, Assayas creepily explored the occult uses of our electronic gadgets. Here he reverts to wilder apocalyptic warnings about the post-literate Martians who are taking over – and because cinephiles are as much at risk from their ray guns as the elderly folk who still read books, he has reason to be concerned. Non-Fiction is pleasant to look at and even better to listen to, but I couldn’t suppress a longing for something a little faster and more furious.