In 1983, Kingsley Amis confided in a letter to Philip Larkin that he was reading nothing for pleasure except the complete works of Dick Francis, in order, in a loop. “I reread them… all the time, crying my eyes out at all the marvellous good sense and decent feeling (not being sarky).”

By that time, Larkin was already out and proud as a Francis devotee, having publicly nominated him as his joint favourite novelist (with Thomas Hardy). In a review in The Observer, Larkin praised “the absolute sureness of his settings” – the brilliantly, if unpleasantly, realised Russian background of Francis’s Trial Run (1978) “simultaneously removed any need to go to Russia along with any desire to” – as well as “the literate jauntiness of style, the unfailing intelligent compassion”. “He is always 20 times more readable than the average Booker entry,” Larkin concluded.

Francis, who died in 2010 at the age of 89, was one of those rare novelists – Lee Child is the only real equivalent today – who seem to appeal equally to people who read only one or two books a year while supine on a beach and to littérateurs such as Amis, Larkin and C P Snow. “Mr Francis... has qualities and gifts which very few novelists begin to possess. In many respects, his books are deeper than so much work which we dignify… by the name of Art,” Snow pronounced in 1973.

For an ex-jockey who turned to writing thrillers in his 40s to pay for a new carpet – then published one a year, every year between 1964 and 1996 – these were giddy critical heights to reach. “He loved the fact that people thought there was intellectual merit in his work,” his son Felix tells me, “though I think he would have found a conversation about his work difficult at that level.”

So, what is the secret of the breadth of appeal Francis, unwittingly and as something of a puzzle to himself, achieved? Obviously, he had the advantage of a thorough knowledge of the racing world, which plays some part in all his thrillers, from his debut Dead Cert (1962) on. Jilly Cooper tells me that racing enthusiasts find his books uniquely authentic – “which is why in my novels, my ongoing hero Rupert Campbell-Black reads only Horse & Hound and Dick Francis”.

Dick Francis in his horse-racing days: riding Fighting Line at the Grand National, 1950 
Dick Francis in his horse-racing days: riding Fighting Line at the Grand National, 1950 CREDIT: Ron Burton
It’s really a matter of style – the Francis prose is sharp, economical, evocative – which is, says Felix, where Francis’s wife, Mary, came in. “Ideas used to pour out of Dad and he’d put them all down, and then Mum would go through the text, and she knew how to get the rhythm of a sentence right,” he says. “Some reviewers have disparagingly said over the years, ‘Oh, the Francis books, they’re just easy reading’ – well, my father and mother worked bloody hard to make them easy reading.”

After Mary’s death in 2000, Felix became his father’s collaborator; for the past decade he has written books marketed as “Dick Francis novels” solo, matching his father’s pace of one per year. What is the main rule to abide by when writing a Dick Francis novel? “They’re about people, not horses,” he says. “Racing is simply the canvas against which you paint the story, and it’s a wonderful medium to write about people, because you have everyone from the Queen down to the man in the bookie’s with the fag hanging out of his mouth.”

Felix’s latest novel, Iced, is a rattling good yarn, with a hero – an ex-jockey turned Cresta Run “rider” – who reluctantly returns to the world of racing when he comes across evidence of sharp practice. It’s the classic Francis formula: the first-person narrator who turns amateur sleuth and makes very dangerous enemies.

It’s these Francis heroes who make the deepest impact on readers, I suspect. Almost invariably on the brink of middle age and damaged in some way – abandoned by their mothers, belittled by their fathers, divorced, or in love with somebody unattainable, made sour by some mutilating accident – they tend to be loners suffering from low self-esteem.

Felix and his father, Dick Francis 
Father and son: Felix and Dick Francis in 2009 CREDIT: Geoff Pugh
But then they get to show their mettle, led by a disinterested sense of justice into a lonely, very violent battle against a powerful adversary who can command plenty of thugs to deal with nosy parkers.

After the final dust-up, although happy endings are not guaranteed, the heroes at least manage to start the journey to realising their self-worth. Can anyone read the final chapter of the marvellous Proof (1984) – in which mild-mannered wine merchant Tony Beach returns home from thwarting the villains and starts to shout his late wife’s name – without, Amis-like, shedding a tear? “I didn’t shout for lack of her but from wanting to tell her,” says Tony, “that for once I felt I had done what I should, that I hadn’t been for ever a coward, that I knew I hadn’t failed her memory.”

I have often wondered if the power of the books stems from Francis’s own real-life transformation. By the time he began to write fiction, he looked set to be remembered for a failure – the Grand National of 1956, at which, riding Devon Loch in the Queen Mother’s colours, he was 30 yards from finishing in record time when the horse collapsed under him.

It was the mystery element of the disaster – was Devon Loch upset by a crowd made unusually giddy by the prospect of a royal win? Did he spook himself with exceptionally powerful flatulence? – that caught the public imagination, and overshadowed Francis’s otherwise outstanding racing career. But he proved that self-reinvention was possible, as it is for his heroes.

Dick Francis pictured with his family: son, Merrick, wife, Mary and Felix 
Honoured: Dick Francis receiving the OBE in 1984 with, from left, son Merrick, wife Mary and son Felix. He was appointed CBE in 2000 CREDIT: ANL/Shutterstock
Certainly, everyone who knew Francis speaks of him in heroic terms. There is no denying his courage – he flew Wellingtons and Lancasters during the Second World War; when asked later if he thought that being a jockey was dangerous, he replied: “At least nobody’s shooting at you” – but it is his decency that is most often emphasised.

“I shall never forget, many years ago, when I was having a horrible time in my life,” Jilly Cooper tells me. “Arriving at Hatchards’ Author of the Year Party, I was taunted by some bitchy female celebrity, whereupon Dick and James Herriot drew me into the lift to protect and comfort me, and told the bitchy celebrity to eff off.” To Francis, loyalty was paramount, and he once missed an opportunity to appear on Parkinson, at the height of the chat show’s prestige, as he had promised to attend an anniversary party for two of his friends.

“Somebody in the production team said: ‘If you turn us down, you’ll never get asked again,’” recalls Felix. “And he said: ‘In that case, I’ll never get asked again.’ And he never was.”

Iced by Felix Francis (Simon & Schuster, £20) is out 16 September 

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