In the 10 years since she switched from writing romantic fiction to taut psychological thrillers, Lisa Jewell has never been busier.

Already, at least six production companies are interested in optioning her latest novel, None Of This Is True, for film or TV adaptation, including a Hollywood contender.

However, the bestselling writer, whose taut thrillers also include The Girls and The Family Upstairs, is not holding her breath.

“I didn’t go to Hollywood, I just take Zoom calls in my bedroom,” she says flatly from her north London home, in her down-to-earth manner. “The place I’m sitting in my bedroom talking to you now is where I was talking to Hollywood producers.

“It is exciting, and I guess if it did actually end up being produced then I might have an excuse to fly over. But these initial conversations are definitely not worth spending thousands of pounds on to fly half way across the world, while it’s still uncertain.”

None Of This Is True centres on podcaster Alix, who crosses paths with Josie who is celebrating her birthday on the same day – it turns out they are birthday twins, both turning 45.

At first, Josie seems unassuming and Alix agrees to feature her on the podcast – but things soon become more sinister as she inveigles her way into Alix’s life, hiding dark secrets which slowly come to light. In typical Jewell style, there are lots of twists in this disturbing story, along with complicated family dynamics.

All of the novelist’s dark thrillers of recent years have attracted interest from production companies, but haven’t yet made it to the screen.

“I do find it frustrating because of the high levels of enthusiasm and energy that are out there at this point. Everyone’s in my face saying they have the vision, the writer, and then life takes over and you get the occasional update a few months down the line, with: ‘Just to let you know, we’re still looking for the right platform’.”

Yet it’s perhaps fair to say London-born Jewell, 55, is taken more seriously now that she writes thrillers, since switching genre from a successful romantic fiction career (her bestsellers in those days included Ralph’s Party and Vince And Joy) a decade ago.

“I feel far removed from that,” she reflects. “I do think writing those books was just something I was only capable of at that point in my life. That’s just the person I was at the time, who enjoyed writing those novels. I couldn’t do it now, even if someone said, ‘Here’s a cheque for a million pounds, write me a lovely romcom’.

“I don’t know if it was moving fully into psychological thrillers that led to me being taken more seriously,” she continues, “or if it was just a long journey that happened to go into me moving into that genre.”

She believes there are still literary snobs out there though, who don’t take psychological thrillers seriously.

“I do wonder if I have a ceiling in terms of sales because of preconceptions people have about female commercial thriller writers, or Lisa Jewell, because she used to write chick lit.”

But there have been breakthrough books for female thriller writers, she points out, citing The Girl On The Train by Paula Hawkins and Gone Girl by Gillian Flynn.

“But they are women who came from the left field and didn’t have a brand or reputation, so people felt like they could leave that snobbishness behind because it was a new kid on the block.”

None Of This Is True is currently No 2 in the hardback fiction book charts and at the top of the Audiobook charts, so Jewell has nothing to prove.

She wrote it in six months, penning 2,000 words a day, knowing that she had her debut Marvel novel about one of its characters, Jessica Jones, to deliver the same year to a different publisher in a different genre.

“She’s a private eye anyway, so it fits in with my genre, but they wanted to make it like a Lisa Jewell novel about a Marvel character. I thought I would be able to knock that one out in six months as well, but I’m still here a year later, rewriting and trying to get it right.”

She doubts the Marvel book is destined for the screen, as a series featuring Jessica Jones, starring Krysten Ritter, already streamed on Netflix from 2015-2019.

After a holiday, she’ll be starting her next psychological thriller in September. But juggling family life with husband, software consultant Jascha Gordon, and daughters Amelie, 20 and Evie, 16, has been more challenging with her schedule this year.

“This is the first year that my children have been aware of me working, because I’ve always managed to fit it in in school hours and around school holidays and to close my laptop the minute they got back from school or the minute the holidays start,” says Jewell. “This year I haven’t been able to take any time out, so I’m living in my bedroom because I don’t have an office. If they physically see Mum, then I’m doomed.”

When she’s on tour or at book festivals, she still sometimes gets starstruck at the other authors she meets.

“The last one was Colleen Hoover. I did her book bonanza, a writers’ convention in Texas where she lives. I got to do a panel with her. She’s unbelievable. I get really weird around people who are more important than me.

“If I’m in a room at a book event and there’s somebody really famous across the room, I would never approach them. I remember my friend dragging me along to meet Zadie Smith at a book event and just thinking, ‘I can’t breathe, I can’t speak, what am I supposed to say to Zadie Smith!?’”

To switch off, she watches TV – often thrillers but also some reality shows: “I have TV that I watch with my eldest daughter, TV that I watch with my husband, and TV that I watch on my own.”

She’s not a great one for fitness regimes after spending all day on the computer, she concedes.

“I used to be a regular gym-goer, then I stopped one summer because I couldn’t get any childcare and then when the children went back to school, I couldn’t face going back to the gym. And I haven’t done any exercise since. That was about 10 years ago.”

But, she doesn’t wallow in the psychological stress she creates for her fictional characters when she finishes work for the day.

“I don’t feel the darkness. It doesn’t come from my heart, it comes from my head. I want to explore the effect of darkness on people,” she says.

“If you were to sit in a room full of female writers of psychological thrillers, you would think we were the most well-adjusted, normal, rounded, down to earth people. You have to be grounded and have a clear vision.”

None Of This Is True by Lisa Jewell is published by Century, priced £20. Available now.