Jonathan Coe takes himself off to a classical concert when he’s stuck with his writing. Some authors walk it out, or nap to get around a mental brick wall, but for Coe, who at 63 is publishing his 15th novel, the experience of “sitting there for two or three hours with your thoughts wandering, but in a disciplined way because the music is guiding them” can help resolve the toughest of literary puzzles. The process works particularly well, he adds mildly, at those concerts “where you’re not really into the music”.

For Coe, this approach to problem solving was especially necessary during the writing of The Proof of My Innocence, a hugely enjoyable, genre-busting novel set during the 49 days of Liz Truss’s premiership. The book, which is divided into three discrete sections, is a murder mystery, a piece of dark academia and an experiment in autofiction. Like so much of Coe’s writing, it takes a big, ambitious swing at the recent past – all the venom, absurdity and sentimentality of British political life since the pandemic – and metabolises it to bring about something like meaning. Coe did this most famously for the Thatcher years in his hit novel of 1994, What a Carve Up!, and more recently in Middle England, his attempt to explain to himself as much as to anyone else why so many people had voted for Brexit. In The Proof of My Innocence, Coe’s project was to examine the decades-long rightwards drift of the Conservative party and the polarisation of public discourse; the fact, as he puts it, that “what’s different about Edward Heath and Harold Wilson in the 1970s and, say, Keir Starmer and Liz Truss now, is that [their] narratives don’t intersect at all. Which is alarming, I think. If we can’t agree on any form of shared truth, then it’s very difficult to have public conversations about anything.” A description, perhaps, that makes the book sound rather serious. Because it’s Coe, of course, the whole thing is as light as a souffle and tremendously funny.

In fact, Truss as a background condition only came about later in his thought process. In the first instance, says Coe, it was the challenge of trying a new genre that appealed to him. The novel, which follows the dire fortunes of a leftwing blogger who attends a rightwing conference in a country hotel, is structured around a central mystery. “I’d flirted with detective fiction in What a Carve Up! and in Number 11, and really enjoyed it – it’s very challenging because you can’t let yourself off the hook. The plot can’t dissolve into meaningful ambiguity, there has to be a resolution, because that’s what people are reading it for.”

All genre writing, says Coe, is “highly disciplined”, and he has enormous respect for the crime writers who work exclusively in this mode. “You have to spin a lot of plates at the same time and the great crime writers do this yearly. I’m slack-jawed with admiration for the way they do it, because you have to have a very special kind of mind.”

What is so arresting about The Proof of My Innocence is the other genres the book takes in its stride. Coe likes to keep an eye on the Amazon top 100 and BookTok – “to know what people are actually reading” – and the sales of cosy crime, and cosy romance, caught his eye. “A book called The Pumpkin Spice Cafe had been lodged in the Amazon top 10 for the last two weeks,” he says. These are the literary versions of Hallmark movies, safe reads, says Coe, “because people for obvious reasons are reading for comfort, which is not the only reason for reading, but in a fairly mixed-up world people increasingly turn to it. I want to try and give readers the satisfactions and comforts of writing in this book, which is why I try to enter wholeheartedly into the conventions and give them a country house murder and a secret passage. But I try and do slightly more wacky things around the edges at the same time.”

The wacky things include two gen Z sleuths; a brilliant, tank-like detective called Prudence who gets wasted and eats her own bodyweight in dessert before effortlessly solving the crime; and a creepy, cult-like Conservative shadow movement that has been playing a long game to put a rightwing nutter in No 10. This is prescient of Coe, given the exposure this US election season has given to Project 2025, the shadowy rightwing movement hell-bent on having Donald Trump elected so he can fire half the civil service and replace them with political appointees. In Coe’s novel, the roots of the movement go back to a Cambridge professor called Sir Emeric Coutts, who “had read Adam Smith and Edmund Burke at an early age and had soon concluded that in an ideal society the duty of the politician was simply to stand back and interfere as little as possible in the equitable, harmonious workings of the free market”. Half a century later this conviction results in Truss as prime minister and, as the novel puts it, the feeling that “everything seemed to have become unmoored from reality”.

Alongside the political story are the traditional pleasures of a Coe production: a perfectly rendered and warmly sketched outline of family life, including a twentysomething on a zero-hours contract feeling stifled in her parental home, an arms-length adoptive dad doing his best, minor marital strife, and a young man, based on the author, struggling in his first year at Cambridge. For the gen Z characters, Coe had his own twentysomething daughters to draw inspiration from, not least their teenage love of the TV show Friends, storylines from which crop up in the novel as a kind of sardonic shadow text. Coe’s aim is to interrogate nostalgia, its dangers and appeal to those on all sides of the political divide, and across the generations. “I’m quite fascinated by the love for Friends by gen Z,” he says, “in the same way that I am by the way people turn to cosy crime; it’s a safe place. And I watched every episode of Friends with my daughters, twice, when they were in their teens. It was clear that the 1990s was a safe zone for them, because it was just about pre-internet and pre-mobiles. And that gave me the whole idea for the theme that runs through the book of being nostalgic for a time before you were born.”

Coe, who was born near Bromsgrove, south-west Birmingham, to a research physicist father and music teacher mother, understands that “you don’t want to go back and live in those worlds, because there’s so much wrong with them. But the way they’re presented on screen can be an incredible balm for the soul.” This nostalgia is particularly appealing for writers who came of age when the cost of living was cheap and the social safety net generous. After Cambridge, Coe moved to London. “For me as a white, straight male it was a very good time, because society was really geared up to looking after my interests,” he says. “I came to London in the 80s when Thatcherism was only just starting and I was able to start my career as a writer in a way that wouldn’t be possible now.” He moved into a shared council house with a bunch of medical students in Bermondsey, south-east London, and his overheads were enough to make someone in the equivalent position today weep. “I paid £8 a week,” says Coe, “and I was signing on and getting £30 a week and living on that in London, quite comfortably in a way. And that gave me the leisure to become a writer. That kind of safety net, that entry point into a creative life, is not available to young writers or musicians now.”

After the promise of Cambridge, were his parents dismayed by his lifestyle? “My parents were never very ambitious people. Comfortable, middle-class suburbia was their aspiration, really. So they always assumed that I would go into academia and have a steady job as an English lecturer in some nice Russell Group university. That was the aspiration. Well into my late 30s my father was still clipping out job adverts from the papers and sending them to me and saying ‘this looks worth applying for’. Quite rightly, they didn’t think that writing novels was a viable career path, really. And it’s not in many ways. Through luck as much as anything else I’ve managed to spin it out. I was first published in 87, so 37 years now.”