Now is a fretful time for Jonathan Lee. The release of his latest and third novel, High Dive, which closes with the 1984 bombing of the Grand Hotel in Brighton, is finally upon him. It is fiction spun out of an actual and indeed momentous event. Has he got the Brighton of that time right? The idioms? The feel of the Lanes? And what about the book’s other main locus, Catholic Northern Ireland?

Maybe he is just a fretful sort. He concedes that one of his three main characters, the skittish deputy General Manager of the beachfront hotel, Philip Finch, who goes by the name Moose, is a version of himself. “All writers try to smuggle themselves into the novels,” he tells me in the airy top-floor apartment that he shares these days with his wife in Brooklyn, New York. “There’s definitely some of the novelist in him [Moose], constantly being on edge, always worried about what people are going to think.”

Abandoned by a wayward wife after “an American” took her fancy, Moose has his late-teen daughter, Freya, to worry about. She can’t be filling in behind reception for ever. There is also the matter of his getting promoted if the Conservative Party Conference around the corner goes well and “the Lady” – Mrs T – leaves his hotel content. He knows he has never quite lived up to the expectations people once had of him as a person and athlete, including as a diver. This is his moment to redeem himself.

Lee, a Brit who moved to New York three and a half years ago, doesn’t need redeeming, but he admits to pressure. In 2011, he gave up a solid career at Freshfields, one of London’s “magic circle” of law firms, and felt the cold draft of his family’s surprise if not quite disapproval. “I felt very ungrateful at the time – that I wasn’t enjoying it [the law] as much as I should.” His first two books, Joy and Who is Mr Satoshi? pleased the critics but didn’t jam the revolving doors at Blackstones. “I was writing this book at a time of relatively low confidence in my craft,” Lee admits.

(Maria Spann)

Yet, you get the sense that secretly Lee is a bit excited about this one. His wife just read it, chuckling often, but refusing to say which parts amused her. It is one of the surprises of the book – which opens with the brutal initiation into the Provisional IRA of Dan, the third of the three protagonists, and ends with the front of the Grand being ripped out – that it is frequently funny. A comic historical bombing yarn is hard to pull off. There is a marvellous passage towards the end featuring Moose trying to save, in his mind, Sir Keith Joseph, the then education secretary, from an especially eccentric hotel regular, not realising that Sir Keith is rather taken with the man.

The author is happy that his cast keeps popping into his head, even now. That didn’t happen with his first two books. “I have thoughts about Moose, Freya and Dan on a weekly basis. I find myself wondering, ‘What would they do in this situation?’,” he says. But there is also his feeling that High Dive may matter a little bit. He is hardly the first author to insinuate fictional characters and plot detours into events in history. But he may be the first to give the Brighton bombing this treatment. And it is an incident that traditional historians have been rather neglectful of. “If you do it well, fiction can maybe have a purpose in terms of opening up a period of history in a way that non-fiction cannot,” Lee says.

But is this necessary with history that’s so fresh? Certainly, Lee responds. Recent doesn’t always mean familiar. “I came to realise,” he offers, “that that thing people say about nothing being more remote than the recent past holds true”. It may be especially so when it comes to the “Troubles” and the IRA. He was working in central London in 2005 when the bus and King’s Cross bombings happened and nobody seemed to make the connection with the mainland IRA bombings that had happened just a relatively short time before. “I think there has been a collective sort of forgetting of that time.”

Few IRA attempts on the mainland were as dramatic. “I was obviously interested in knife-edge points, turning points in stories, whether personal or political. That moment on 12 October 1984 could have come out so differently. It was the most ambitious assassination attempt since the Gunpowder Plot. It came extremely close to wiping out Thatcher and pretty much the entire Cabinet. Instead, through a combination of happenstance and the kind of person she was, she walked out of the rubble and announced that the conference was going ahead as planned. And her personal popularity goes up.”

Brooklyn is a long way from Brighton and Belfast but moving there was strangely helpful, Lee says, because it precipitated the moment when he stopped researching and began writing. “It’s a tipping point. It comes to me like a creeping guilt, like a sense that I am not really writing,” he explains. “I am a master procrastinator like most novelists. But a point comes when you need to get into the book and get something on the page – to get a sense of what was right.”

That earlier research took him to Belfast, a city he knew a little from work he had done there as a lawyer, and to the long-ago rebuilt Grand in Brighton. But the hotel wasn’t quite unfamiliar. As a boy, his family used to make day trips from Guildford to Brighton and take tea in the hotel. “I remember seeing strange characters at the bar, a local eccentric in a red jacket.” He becomes “Captain” in the book, a local gay figure and the same man who smuggles himself into the Conservative cocktail party and charms Sir Keith.

But Lee’s biggest the breakthrough came when he fell upon reports that the man identified as the Brighton bomber, Patrick Magee, and sent to prison for it – later to be released as part of the Good Friday Agreement – might have had assistance in planting the bomb from a mysterious second figure that no one seems to know anything about. Thus Lee was able to recruit and inhabit this barely sketched man as his own. He is Dan. “I was very resistant to the idea of inhabiting Magee’s thoughts. I didn’t feel able to put myself in his thoughts. The second bomber gave me my way in.”

As for “the Lady”, we see her only for a moment when Moose finds himself pushed to the ground in the scrum as she enters his hotel and glimpses a lower leg. “The roundness of her ankles surprised him.”