Moments of horror from your past can mentally scar many people - but not bestselling novelist Michael Cordy. To him, such traumas have the potential to inspire his next high-octane, high concept thriller.

The author - four of whose books have now been sold to Hollywood - remembers a time as a child, growing up in Uganda at the height of Idi Amin's terrifying repression, when the family was heading home and their driver warned him, 'Don't look to your left!'

"Well, of course," he recalls, "being a child, what do you do? So I looked to my left."

"We were on our way back to Jinja, near to the Speke Monument which marks the source of the Nile, and along the banks of Lake Victoria there were crocodiles and what the soldiers were doing was shooting people dead and pushing them into the water. It was at a time when our next door neighbour had just vanished but, as a child, I couldn't understand it."

His storytelling since, he says, has always been his way of making sense of the world.

"I know someone who has OCD and he is constantly beset with horrible thoughts of what might happen, which is not nice for him, but I told him, 'I make a living out of that!'

"Horrible thoughts are just thoughts. They have no morality. We are judged by what we do, not what we think. I relish the worst possible things and look into the darkness and then write about it and find some positive meaning in it."

Nothing in his life has been quite as dark as the first time his infant daughter Phoebe collapsed and stopped breathing because of a rare sleep disorder. But now it has inspired a character in his newest novel, Manhattan Down, where climate terrorists use a sleep 'virus' to put the heart of New York, aka 'The City That Never Sleeps', into a coma, in a bid to wake up world leaders to the threat posed by global warming.

Over lunch in London, Michael, 64, tells me of his horror when his daughter had that first fit: "It was terrifying. She was about one year old and my wife Jenny had taken her to see Phoebe's granny and she had stopped breathing."

Phoebe was taken to hospital and medics checked her heart but could find nothing wrong.

"The first one I saw was some time later and it was equally terrifying." says Michael. "Until we knew what it was."

Doctors were initially puzzled, but after a few more alarming episodes, including once when Phoebe was playing at a friend's house and collapsed backwards hitting her head, they were referred to a paediatric consultant.

Michael recalls: "It's your worst nightmare as a parent. Every time she collapsed you wondered, 'Will she ever wake up again?'. It was really horrible.

"They called the falls 'idiopathic' because they didn't know what was causing them but the consultant immediately raised the prospect of epilepsy, which was alarming. When you go to the doctor with a lump they might well say, 'It's probably nothing, but...' but this consultant went straight to epilepsy, telling us Phoebe would have to wear a crash helmet!"

"I said, 'Surely it's relevant that she only has the seizures when she's under the weather or over-tired?"

After more of Phoebe's hypnagogic hallucinations, including one time when she thought she saw Zeus, Michael and Jenny were eventually given the opportunity to take her to a sleep lab where she had her brain waves scanned and tests revealed she did not have epilepsy.

It was then that another parent suggested the possibility of Reflex Anoxic Seizures (RAS) - non-epileptic events (particularly in infants and pre-school children) that can cause the heart and breathing to stop in response to an unexpected stimulus like pain, shock, fright or, as in Phoebe's case, over-tiredness.

Michael explains: "She's now in her twenties and almost over it. She is better at self-regulating and calming herself down when she reads the signs so I like to say that if your child has got to have something seriously wrong with them, RAS is such not a bad box to tick."

And when he was writing his latest thriller and needed a character who was functional but vulnerable, he turned to Phoebe to get the exact feelings his young heroine would go through when having a seizure.

"I felt a bit guilty about using her condition but she loves it because, like me, she loves story-telling, and she could tell me when I was getting it wrong!"

Michael was born in Ghana, where his father was working, before the family moved to Kenya then settled in Uganda in the 1970s where military ruler Idi Amin was about to become one of the world's most brutal despots.

Michael tells me: "My dad met Amin, briefly, once. He was OK until he just wasn't and it all went pear-shaped pretty quickly. We had to leave the country because, apparently, Amin was nice to him...which I'm told was a warning sign."

The family moved to India, then Cyprus, before Michael continued his education at The King's School, Canterbury, Kent, then at the universities of Leicester and Durham.

Michael recalls: "I had a stammer when I was young, which was not great at boarding school and university, so I learned to self-edit my words and choose words I could say without stammering. I also had long car journeys to boarding school and I would use them to make up stories, so it has always been in me. It's my way of making sense of things.

He began a career in marketing and advertising and says: "I started marketing toilet cleaners and moved from biscuits to books." But the writing bug was always in him and he says: "There was a moment when I was working for Bacardi and I went to Bermuda but I didn't want to go to the beach because I wanted to write stories.

He had an idea about a scientist discovering the DNA of Christ and wife Jenny told him he should take a year off from work to see if he could make it as a novelist.

He jokes, "Well, after a year I had all the right words but, as Eric Morecambe would say, not necessarily in the right order. It took two years before I had it right."

His first book, in 1997, The Miracle Strain, made it to number 5 on the Sunday Times best-sellers list and Disney bought the rights. His second book, Crime Zero, in 1999, was bought by Warner Bros, and his third book Lucifer, in 2001, was another hit.

Then came the worldwide success of Dan Brown's The Da Vinci Code, exploring similar themes to Michael's first book, and the film, starring Tom Hanks, was a global smash.

The names of Michael's first four books were later changed - to the Messiah Code, The Crime Code, the Lucifer Code and The Venus Conspiracy, leading some people to think his books had been inspired by Dan Brown.

He says: "I remember someone saying 'Are you jealous of him?' Well, no, because The Da Vinci Code was such a phenomenon. You have to have a very fragile ego to go, 'I am so offended that I haven't changed the face of British publishing!'

"I do get annoyed, however, when people say, 'Oh, you copied him.' I did it in 1997 and he did it in 2003!'"

He also smiles at those who suggest he should have got Disney to option his first book and kept some control over it rather than let them buy it outright, because he is still waiting for them to make a movie of it, despite coming close four or five times.

He says: "I was paid a lot of money for it - $1.6million. I had been out of work for two years before that so when I was offered that deal I wasn't going to turn it down. Besides, I call our lovely home in Twickenham 'The House that Mickey Mouse bought!"

For the past 10 years Michael has largely stepped away from writing new novels to work in Hollywood, writing screenplays and working to get some of his blockbuster books made into films but he says he found the experience frustrating.

Then, during the pandemic lockdown, Michael, whose books often involve new technology or a rare medical condition, was running in his local park when he got the idea for one about insomnia and he says, "I got my mojo back.

"I was interested in sleep and then I read a book called The Family That Could Not Sleep about an Italian family that had this awful hereditary disease - Fatal Familial Disorder - which only about 30 families in the world have got, and I remember thinking, 'This is amazing,'.

He had previously spoken to a friend who had done a documentary on Extinction Rebellion and how individual climate protesters often have different motivations and he said: "I already had the idea about Phoebe and the sleep labs and, with some weird fuzzy logic, four or five different ideas all came together."

Having written the book, he then had to go to his publishers.

Michael says: "Coming back into the game, having had such success and then a hiatus, you are terrified you might come back and find life has moved on and... 'You're just an old fart....'

"You tell yourself to trust in the book and that if the work's good enough it will be OK but we all know that's not entirely true. If you don't hit the right buttons; if you don't do the right things...

But publisher Bill Scott-Kerr at Transworld was happy to take a read and tell his friend, jokingly, 'It's not rubbish!'

In fact Manhattan Down is Cordy back at his brilliant best and ripe for another Hollywood buy-up.

It has also helped Michael to put his most scary memory behind him.

"Phoebe's condition is kind of sorted now but the shadow it cast is quite real," he says, "and when you choose to write about it you can either make it worse or you kind of exorcise it and make sense of it.

"Good stories have that moment when everything is going awfully and then you fight back and using Phoebe's condition and making her a hero rather than a victim was quite cathartic," he says.

So that's another Cordy thriller with a happy ending. Now for those crocodiles!

Manhattan Down by Michael Cordy (Bantam, £16.99), is out now