ANDREW FFRENCH gets under the covers with our latest Book of the Month, a mind-bending debut from author SJ Watson.

* THE BOOK: EVER had a moment when you had to wrack your brain to remember something – the name of the goalscorer in that classic cup tie, or more importantly the date of your mum’s birthday?

We’ve all had moments when our memories let us down but imagine how life would be if our memories played tricks on us every single day.

That’s precisely what debut author SJ Watson does in his stunning debut novel Before I Go To Sleep, which has stormed the bestseller lists in the UK and the USA and has been sold in 42 ‘territories’ around the world, according to jubilant publishers.

The main premise for the story is a brilliant one. Christine, 47, had a terrible accident many years ago which had a devastating effect on her brain.

Her memory is extremely selective – and wipes out the activities of each day overnight.

So when she wakes up in the morning she is in a state of shock, failing to recognise her husband Ben and her surroundings and has no firm grasp of her personal history.

So that she can make some sort of progress, a therapist called Ed Nash advises her to keep a journal which she completes every night before she goes to sleep.

She keeps the journal secret from her husband because she doesn’t know if she can really trust him and, gradually as her memory starts to improve, she recalls key events from her past life.

She used to live with Ben in a different house, lots of her photos and belongings were once lost in a mysterious fire, she is the mum of a boy called Adam, and her best friend is called Claire.

Christine’s story is told in the first person, so we feel her unease as the story progresses and as she finds out more and more alarming things about her past.

It emerges that she spent a number of years in a mental institution and her husband has been keeping key facts from her past a secret. Like Christine, we begin to wonder if he is doing this to protect her, or does he have some dark, ulterior motive?

The author expertly builds the suspense, drip-feeding the reader clues about Christine’s past as the chapters progress.

Because Christine has a condition that recurs daily, it would be easy to fall into the trap of repeating the same scenarios but Watson avoids this by ensuring that she remembers more and more.

After it begins to emerge that Christine did not really lose her memory in a car crash, but may have been attacked in a hotel room, it becomes impossible to put this book down.

Is husband Ben as kind as he seems, and why is the doctor Ed Nash taking such a personal interest in her case?

There are elements of this novel that make uncomfortable reading – losing your memory is a kind of mental illness after all – and Watson uses his experience of working in the NHS to ensure that certain scenes ring true.

There are also potential technical difficulties of making Christine’s journal such an important element of the narrative but Watson manages to overcome them.

This is a gripping suspense thriller and it is not surprising the rights to the novel have been acquired by film producer Ridley Scott.

When I had finished the 372-page story I was left wanting more.

* THE AUTHOR: STEVE ‘SJ’ Watson was born in the West Midlands in 1971, studied physics at university, and then moved to London where he worked in a number of different hospitals.

In 2009, he was accepted for the first Writing a Novel course at the Faber Academy and the result of his attendance was his debut Before I Go To Sleep.

It is understood that he was introduced to a literary agent on the last night of the course and she agreed to represent him.

The novel was first published last year and is a New York Times and Sunday Times bestseller.

It also won the Crime Writers’ Association Award for Best Debut Novel and the Galaxy National Book Award for Crime Thriller of the Year.

The rights to the novel have been acquired by Ridley Scott’s production company, Scott Free, with Rowan Joffe to direct.

For more information about the author visit * Before I Go To Sleep by SJ Watson is published by Black Swan and is priced £7.99 but you can get it for half price at Waterstones in Oxford or Witney with the voucher available in the the Oxford Mail's entertainments supplement The Guide.