In the closing chapter of John Irving’s epic new novel, Last Night in Twisted River, a character struggles to find the opening line for his latest book. He agonises over it for a morning, then puts it to one side – and 24 hours later hits pay dirt.

Which is considerably quicker than Irving himself. It took the award-winning author no less than two decades to come up with the crucial one line which would allow him to write Twisted River. ‘I’ve lived with these characters and this story longer than I have with any other book,’ says Irving. ‘A story about a cook and his son who become fugitives – that’s been in my head for 20 years. But I never begin a book until I have the last sentence – and this one eluded me for a while. So I wrote a number of other books, because I saw the exact ending to those stories quicker than I saw this one.’

The aforementioned fugitives are Dominic and Daniel Baciagalupo, a father and son team forced to go on the run from a crazed cowboy, after a tragic accident in the New Hampshire town of Twisted River. Spanning five decades, from 1954 to 2005, the novel features many of Irving’s trademark subjects – New England schools, writing, bears, wrestling and, most crucially, death. The three central characters, Dominic, Daniel and their wildman friend Ketchum, are all rich in detail – but then so too are the minor ones. It doesn’t matter how brief an appearance you make in an Irving novel, chances are he’ll give you a back-story.

‘That’s something that comes from the earliest fiction I admired, that made me want to become a novelist in the first place,’ says Irving. ‘Those plotted, usually long novels of the 19th century that had developed characters – even the minor ones – usually with the passing of time as an important component of the story. Dickens, Hardy, Melville, Hawthorne – those guys.’

Like his literary heroes, Irving isn’t afraid to kill off key characters – as all owners of tear-stained copies of The Hotel New Hampshire, A Prayer for Owen Meany et al will testify. Inevitably, over the course of 554 pages, Twisted River has its fair share of tragedy and untimely death. But while it’s fair to say that Disney will never make a film out of an Irving novel, his fondness for devastation makes for compelling reading.

‘My choice is to move or affect a reader emotionally and psychologically, not intellectually,’ says Irving. ‘So the design for many of these novels is brutally straightforward. Namely, here are some characters you care about, and fear that the worst thing imaginable is going to happen to – and in some cases it does.’

When you’ve spent days, or sometimes weeks, growing attached to the characters in a novel, it can be hard to let go. Whether it’s through death, or simply the story coming to an end, the eventual sense of loss is palpable for readers of any good novel. Does Irving miss his characters once he sends off that final draft? ‘Well actually I miss them before I’ve written about them,’ he says. ‘Because I know what’s going to happen to them – I know the fates of all my characters, even before I start writing the story. So with this novel, I knew what was going to happen to Ketchum, I knew when the cowboy was going to catch up with Dominic. So even though I hadn’t written those scenes, it was as if they’d already happened. And in some cases, they were scenes I was dreading the writing of.’

Along with copious praise for his 12 novels to date, Irving has also received a fair amount of criticism. Chiefly for writing about similar subject matters, many of which pertain to his own life – the area he grew up, the schools he attended. For Irving, however, what matters more is the stuff which hasn’t happened to him – at least not outside of his imagination.

‘There is a lot of what I fear in my novels, of what I hope never happens to me but that I feel obsessed by and compelled to write about again and again,’ says Irving. ‘I wouldn’t say the things that have happened to me, the people I’ve known, the schools I went to are as important autobiographically as those things which are recurrent book-to-book, which never happened to me. In other words the death of a child – I have not, thank God, lost one – but I think about it all the time. So that’s also autobiographical, not because it happened but because I fear it.’

It’s easy to see aspects of Irving in the character of Daniel, the young boy in Twisted River who grows up to be a best-selling novelist and screenwriter. At one point, during one of his many references to the way novelists think and feel, Daniel says, ‘all writers are outsiders’. Given the non-rose tinted way Irving writes about his native America, it seems safe to assume he too feels that way? ‘Yes, very much so,’ he answers. ‘I don’t think most writers are as attached to their birth countries, or the countries they live in, in the same way that regular citizens are. A part of being a writer is one of necessary detachment, you have to be able to see yourself standing outside the society you live in, looking in. You don’t feel as if you’re a member of the tribe you’re observing.’

Last Night in Twisted River is out now, published by Bloomsbury.