Steven Spielberg has optioned his book series for the big screen, but if Osman is starstruck by this turn of events, he isn’t showing it.

The 52-year-old creator of quizzes and former co-host of BBC’s Pointless appears to be taking the whole thing in his stride. He has sold 10 million copies of his Thursday Murder Club series, grossing more than £25million.

The fourth novel, The Last Devil To Die, was published last week, and there are rumours of another four-book deal with Penguin worth £10million.

He admits: “I’m completely blown away by it all. I have had a career in telly where I’ve had successes but lots of failures as well. You learn to appreciate the successes as there is so much luck involved. When you have a success you thank the fates and just enjoy the ride.”

Asked about the movie, he shrugs and will only say that actors in their 50s rather than 70s will play the novels’ main characters, to allow for the franchise to evolve. He says he has no clue on casting.

He smiles: “If people stop me in the street I know there is only one of two things they are going to ask me.

“They’re going to ask me how Fulham are doing (he is a fan) or they are going to tell me who should be in the first Thursday Murder Club film.

“It’s a lovely parlour game now. There are so many amazing older actors, but it’s up to Spielberg, not me.”

For the uninitiated, The Thursday Murder Club consists of Elizabeth, a former spy; Joyce, a former nurse; Ibrahim, a psychiatrist; and Ron, an ex trades union official, who meet up every week to investigate unsolved murders.

The writer famously based the location in the books on his mother Brenda’s retirement home in Sussex, claiming that the fictional Cooper’s Chase is just like hers – without the crime capers. When I say I’d love to live in Cooper’s Chase myself, he agrees fervently: “Oh me too. It’s great. My mum’s place is such a brilliant place to live. It’s so full of mischief, gossip and trouble.”

Describing himself as a full-time writer now, he feels as if he has moved on from TV. He no longer has the time either.

“Writing a novel is insane, it’s really hard work. Being a TV presenter was the world’s easiest job. Suddenly I’m having to work for a living. But seeing the reaction to it does make it all worthwhile and I love it. I am not a TV presenter anymore, I am definitively a writer.”

There is a hint of heartbreak close to home in the latest book.

He hesitates: “The latest book is set in the world of heroin importation – and antiques. There is an awful lot going on.

“I have the joy of these four characters, all of whom are so mischievous. They represent something very special about being older and the things you can do.

“But to have that fun, I have to pay the tax on that – which is to show the truth as well: grief, heartbreak and infirmity. In the latest book there are troubles and heartache close to home. There are tears but a lot of laughs. I try and write about unlikely friends and that you can have new adventures at any time of life.”

He says his fertile imagination for writing was fired up as a child by his adored maternal grandfather, a police officer.

“He was called Thomas but everyone called him Fred, in the way of that generation. Every time we walked around
the streets of Brighton he’d tell me who’d been murdered, and what went on behind certain lock-up garages.

“So my head has always been filled with stories of crime from a young age.”

Richard and his brother Mat Osman, a bass guitarist and founding member of Britpop band Suede, were raised by single mum Brenda near Haywards Heath, West Sussex, after their father abandoned the family when he was nine.

Richard vividly remembers being sat down by his father, David, who confessed that he had fallen in love with someone else and was leaving. “It was the worst thing that ever happened to me,” he has said. “He just left and I didn’t see him again for 20 years – that’s hard.” He recalls: “My grandfather was the main male role model in my life. He was an incredibly strong, tough guy, but incredibly kind as well.”

His experiences made him determined to be there for his own children when he got divorced in 2007. “I wanted to spend as much time as possible with them and I have done.

“They are in their 20s (Ruby is 25 and Sonny is 23) so they are now what I describe as self-funding. They come around for boardgames nights and my daughter lives just around the corner.

“It’s lovely seeing them build their own lives and still wanting me to be part of that.” Asked what they think of his success, he shrugs: “I think they are proud which is nice. My son has never read the books.”

Three years ago he met his second wife, the Doctor Who actor and comedian Ingrid Oliver. It was an unexpected but joyful curved ball for him after dating for most of his 40s. “I was always looking for The One,” he adds.

He says: “She was a guest on House Of Games one summer and she had moved in by October. I proposed on holiday last year and we got married in December.”

His dedication at the foreword of the third book reflects his deep feelings for her: “To Ingrid. I was waiting for you.”

He continues: “We met at just the right time. We just laugh all the time and that’s a world I like to be in.”

He is ambivalent about fame: “People used to stare at me in the street anyway because I’m 6ft 7in, but when fame came with Pointless, I was about 40, and fairly fully formed. It’s been a positive thing for me. I’ve always quite enjoyed it.”

● Order The Last Devil To Die by Richard Osman (Penguin Books Ltd, £22) from Express Bookshop, £19.80. Visit expressbookshop.com or call the Express Bookshop on 020 3176 3832. Free UK P&P on online orders over £25. Also available as an audiobook narrated by Fiona Shaw