She left school at 16 with no qualifications and worked as a ­kissogram girl and a barmaid before falling into an unhappy marriage to a controlling man 27 years her senior.

But through the tough times Samantha’s love of writing kept her going and now, an incredible 40 years after she first started scribbling away in her childhood bedroom, she has landed a four-book deal.

What is more, the film of one of those books, The Stranger In Our Bed, starring Downton actress Samantha Bond, premiered on American TV last month and will be released in Britain this September.

The novelist says: “I always wanted to ­follow my dream of being a full-time author, but I was distracted by just surviving. I spent a lot of time making ends meet. My childhood wasn’t easy and I went through my entire life thinking I wasn’t capable or intelligent enough.

“Teachers at school treated me like I was stupid. Then my husband treated me like I was stupid. Nobody believed in me, so when HarperCollins wanted to publish my work, I could hardly take it in. To get a deal with a big publishing house that everyone has heard of was what I’d been aiming for all my life.”

Samantha, 56, grew up in Manchester with her parents Agnes, a hospital orderly and Laurence, a window cleaner, but it was a miserable existence.

“It was very unstable,” Samantha admits. “I was the youngest of seven children and my father was a violent alcoholic, so education wasn’t on the list of my ­priorities, I was more ­concerned with the idea of surviving every day.

“He was violent towards all of us and very erratic and controlling. I’d hide away and lose myself in writing. My mother was an eclectic reader, so there’d always be books from the library and she’d go to the market and come back with stacks of books.

“One time she came home with John Fowles’s The Collector. I read it and I was hooked. It left me with a new-found passion for reading and writing. Until then my teachers at school actually thought that I couldn’t read. It wasn’t that I couldn’t, I just didn’t like the children’s books they were giving me.”

After seeing an advertisement, Samantha wrote a short story for a competition run by the television series Tales Of The Unexpected and proudly showed it to one of her teachers at school.

But instead of praising her initiative, he crushed her ambitions. “He said it was too grown-up for my age,” Samantha recalls sadly. “His criticism made me feel so bad it put me off entering.”

Eventually the rows and physical abuse at home forced her to move in with her older sister Adele. Needing to earn money, the teenager took a variety of jobs, including secretarial and bar work. She even worked as a kissogram girl, visiting local pubs to ­perform saucy song and dance routines.

So when she met used car dealer Jack Stone, who was 27 years her senior, he seemed to provide the security and stability she needed and she moved in with him.

“I was a child and so quiet when I met him and he seemed sophisticated and very nice, but as I grew up, I realised he wasn’t at all.” Jack tried to stop the one thing Samantha had of her own – her writing. “He’d say, “Why do you want to do that?” He even used to complain when I was reading a book. He’d say, “Let’s watch some TV together instead.”

“But my urge to write never went away. It was like an itch in the back of my brain; I’d constantly be thinking of stories.”

After Samantha gave birth to their ­daughter Linzi, she began writing again, snatching moments here and there while the baby slept. And in 1999, aged 33, she plucked up the courage to enrol at Bolton University to study for a BA in English and Writing for Performance.

After university she worked as a teacher, quickly rising to Head of Drama, but still her dream was to be a writer.

“I sent stories out for years and got ­rejection after rejection, but I was stubborn, I wouldn’t give up and I just kept on trying,” she says. Finally, in 2007, she self-published her first novel, Killing Kiss, under the pen name Paigan Stone.

She won the Silver Award for Best Horror Novel with American literary magazine Foreword. But not ­everyone was impressed. Her husband flicked through it and then sneered.

“He picked it up and said: ‘You write like a 12-year-old.’ I was so upset and hurt,” she recalls.

But she was on her way. Killing Kiss led to a deal with a small horror and sci-fi ­publisher. The money it paid was not enough to live on, so she gave up her full-time job and became a supply teacher to free up more writing time.

Again, Jack was unsupportive. She says: “After my first book was published, I picked up some followers on social media. He insisted on knowing everything about where I went and he insisted on owning my mobile phone so he could see who I’d been ­talking to.

“I was starved of affection – he never told me loved me until the day I left. He’d tell me I hadn’t aged well and badger me about my weight. He made me feel worthless.” Eventually she plucked up the courage to leave Jack, who died in 2019.

But after that initial success, Samantha grew in confidence and wrote more than 20 novels under the pen name Sam Stone. She oversaw the 2013 Doctor Who spin-off film White Witch Of Devil’s End and hosted her own show on Lincolnshire’s Siren Radio.

Eventually she married again… to fellow author David J Howe whom she met at a fantasy books convention. Having reached her 50s, her dream of working as a full-time writer seemed more elusive than ever.

But everything changed when Samantha wrote the psychological thriller, The Stranger In Our Bed. It was quickly snapped up by HarperCollins One More Chapter and ­published in February 2020, hitting the Number One slot in the USA Today book charts.