Before I Go to Sleep is a 2014 mystery psychological thriller film written and directed by Rowan Joffé and based on the 2011 novel of the same name by S. J.

The man explains that he is her husband, Ben, and that she suffered severe brain damage from a car accident fourteen years earlier, resulting in her having no memory of her life from her early twenties onwards.

Christine receives treatment from Mike Nasch, a neuropsychologist, who gives her a camera to record her thoughts and progress each day.

Nasch reveals that her memory loss occurred after she was attacked and left for dead near an airport hotel; they both surmise that Ben tells Christine it was due to a car accident to avoid upsetting her.

Christine learns that, several years after her attack, Ben had placed her in an assisted care facility and divorced her, then had a change of heart and brought her home to live with him.

In the letter, Ben tells Christine that he loves her, but that he had to leave her for Adam’s sake, as he had begun to be afraid of her.

The next morning, Christine again awakens with no memory but she finds the camera and sees her entry saying she loves "Ben" and wants to make a life with him.

Mike deletes the videos on her camera and states that he is no longer interested in playing the part of Ben.

She sets off the hotel fire alarm then flees, and is seen telling her story on the camera while waiting in an ambulance.

On 1 May 2011, Ridley Scott bought the film rights of the novel Before I Go to Sleep by S. J. Watson, and hired Rowan Joffé to direct and write the script.

The website's critical consensus reads, "If it doesn't completely avoid thriller clichés, Before I Go to Sleep still offers a stylish, fast-paced, and well-acted diversion.

[17] "Christopher Nolan's 2000 brain-twister Memento starred Guy Pearce as a man with a similar malady.

Writing for Daily Star, critic Andy Lea said in a positive review that "Kidman puts in a chilling performance as the frail but determined Christine.