ANTHONY Horowitz pauses for a long moment when I suggest his lifelong admiration, obsession even, with James Bond, Sherlock Holmes and Tintin, three characters who have cropped up time and again during his fabulously successful career, might be rooted deep in his psyche. After all, having endured a deeply unhappy childhood – overweight and sent away to be bullied and lonely at a miserable boarding school – the prolific author and screenwriter was just 21 when he lost his father to cancer.

Not only was the family traumatised, but within days it emerged businessman Mark Horowitz had died owing many millions of pounds and, with creditors knocking at the door, a comfortable existence was turned on its head when they discovered he had also transferred a vast sum of money to a Swiss bank account. The cash was never traced, it remains a mystery to this day, and young Anthony’s life, and that of his mother and two siblings, would never be the same again.

“I think it is true to say I always felt on my own and have felt on my own for a lot of my life and these are three characters who to a large extent are on their own,” he says today.

“It’s not that they are orphans particularly, and I certainly don’t associate the death of my father with my writing, although it’s true the first sentence of my first Alex Rider novel Stormbreaker – “When the doorbell rings at three in the morning, it’s never good news” – is a memory of his death. So maybe it is some kind of father displacement going on?

“What appeals about Bond and Holmes and Tintin is that they’re not grounded exactly. They’re always outsiders and maybe that’s what I feel – that’s the connection.”

Yet surely success – the hit Alex Rider series about a teenage MI6 agent (orphaned, since you ask), two James Bond novels with a third to come, of which more shortly, 16 years of ITV drama Foyle’s War, his acclaimed Sherlock Holmes books and a recent series of bestselling whodunits, to name just a few – and the accompanying fame and fortune have, despite a sense of dislocation in his work, made him the ultimate literary insider? Another pause. “I’m not. Success has given me pleasure and the fact people read my books makes me happy but I’ve often felt I am on my own.”

He smiles: “I always say my writing has saved me from myself.” Sadly, his father was not supportive of Anthony’s childhood ambition. “He ridiculed me and was so cruel about the chances of my having any success, it’s my unhappiest memory of him. But from the moment I discovered the desire to be a writer aged ten, I was never in any doubt,” he explains.

Although many successful people lose their parents young, the author insists something more fundamental drives him. “Whether it was my bizarre family, the horrible prep school, the bounce of selfdoubt in every way, even into my 20s, in just the same way as a fish needs water, I needed writing.That’s it. Everything is writing.”

FOR many people, such huge expectations might have set up disappointment, but Anthony continues: “I write because I’m excited by the story I’m telling. How would I keep sane with the amount of work I do and the hours I put in if I didn’t have that excitement and optimism?

“Alex Rider was my first really successful book in 2001 and it sold something like 25,000 copies, which was 15,000 copies more than I’d ever sold before. Did that particularly change my life? Well, it made me more comfortable and secure but I was still by myself in a room. I wasn’t going to flash parties or jet-setting or anything else. My life’s a fairly simple one, actually. One of the things about writing is that you’ve got to have utter self-belief. That’s different to being boastful.”

So did his father’s death alter anything? Might he have led an idle, privileged life without that shock of looming poverty?

“I can tell you without any question at all that I would’ve written. I was born to write. Even as I say that it makes me feel a bit cheesy but it’s the truth,” he smiles.

“I am not going to say I was happier in life after my father died, though my mother was certainly happier, he had badly hurt her with his financial manoeuvring and the fact he’d basically taken all her money with him.

“For myself, I felt a blankness, a sense of dismay that I wasn’t more upset. But obviously it impacted on me because of that first sentence of Stormbreaker. It was a big moment but then the death of your father always is. If he had lived” – another long pause – “it’s hard to know what difference it would have made. I wish he had… maybe I’d have been able to understand him better.”

Anthony, who has two grown-up sons, Nicholas and Cass, with wife Jill Green, and splits his time between London and the Suffolk coast, adds: “I’ve tried hard to be a different father to my children but my favourite lines of poetry are Philip Larkin’s ‘They f*** you up your mum and dad…’ so I would never call myself a perfect father.”

All of which segues perfectly into the dramatic opening of his latest – and, sadly, last – Bond novel,WithA MindTo Kill: a quite brilliant set-piece at M’s funeral with one man missing from the graveside: the traitor, now in custody and accused of the intelligence chief’s murder – 007 himself.

We are talking in the early autumn and the author, fit and tanned and far belying his 66 years, is limited in what he can reveal about his new Bond. He is the fourth author in recent years to be invited by Fleming’s estate to write an authorised Bond novel and the only recent novelist to do more than one.

As his lockdown-bought Labrador retriever Chase snuffles around our feet – “All my life I’ve had dogs, the one aphorism I hope to be remembered for is ‘a dog is a mistake you never regret'” – he can say: “I promise you there will be some great surprises… but Bond is a world in which you can get into trouble all too easily if you say the wrong thing.

“It’s a minefield! Ask me what my favourite Bond film is and I’ll tell you I like them all equally. But I wanted a sense of trilogy in my books: my first, Trigger Mortis, was set during the middle of Bond’s career, the second, Forever And A Day, at the start, and the new one is the end.”

Does that mean With A Mind To Kill – “In a mission where treachery is all around and one false move means death, Bond must grapple with the darkest questions about himself,” promises the appetite-whetting blurb – features the threat of retirement? “It’s just that. It’s a very different book in tone to the first two. The truth is it’s difficult to think up ideas that are better than Fleming’s. But if you move the goalposts and come up with a fresh territory then there’s a whole new ground to explore.

“So this is a more psychological Bond, it’s darker, and the early reactions have been great. I’m really excited about it and proud the estate has come back to me to do two more. It’s genuinely been a labour of love; Bond has been so important to me.”

It was this love that helped inspire Anthony’s Alex Rider series, returning to Amazon Prime in the New Year for a second series with Otto Farrant as the teenage MI6 recruit (think young Bond) and Toby Stephens as baddie Damian Cray, and produced by his wife Jill. Fleming, saysAnthony, has always been under-estimated.”Apart from the fact Bond himself is such an extraordinarily original construct, and his world is so well done, they are written in a way that makes you feel sweat come to the palms of your hands.