Ich. Darf. Nicht. Schlafen.

In a very real way, our memories are who we are - our identities as individuals depend in an almost terrifying way upon our ability to remember what we do (and what we've done), why we do it, and whom we love. That's why the notion of memory-making (and losing) looms so very large in the art we create. In the cinematic realm alone, characters whose memories are sorely compromised have starred in thrillers (Memento), romantic comedies (50 First Dates) and weepies (The Notebook). Before I Go To Sleep, based on the novel by S.J. Watson, is a chilling if not entirely effective blend of family drama and thriller, trading on the heartache and horror that comes with losing oneself every single day.

Christine (Nicole Kidman) wakes up every morning with no memory of the last fifteen years of her life. Ben (Colin Firth), the stranger who shares her life and bed, informs her that he is her husband and that she lost her ability to make new memories after a bad car accident several years ago. Any attempt to forge lasting memories seems futile - and yet, Christine tries. She receives a phone call from Dr. Nasch (Mark Strong), a neurologist who assures her that they've been working to improve her condition. He reminds her that she's been keeping a video diary every day: one that, upon review, suggests that Ben is not telling her the whole truth about their shared life and history.

It's to writer-director Rowan Joffe's credit that he mostly manages to make a very personal - and inevitably repetitive - journey of discovery both cinematic and chilling. As Christine awakes each day with her memory reset, Joffe finds inventive and intriguing ways to ramp up the spinetingling alienation she feels from her own life and husband. He captures Christine's terror, doubt and paranoia in the shuddery footage she takes of herself while hidden away in the bathroom from a husband she doesn't recognise. As the wheels within the narrative spin and turn, Joffe's camera makes villains and heroes out of everybody: Ben, in particular, shifts from one to the other on an almost daily basis, as Christine doubts and then trusts the love this man must have for her to stay by her side for so many years.

Unfortunately, Joffe can't quite sustain the tension throughout - the film sags noticeably in parts, as Christine flounders miserably between very few choices. There are many twists, as she uncovers people and secrets in her past that will inevitably disappear from her grasp within a day, including a final doozy of a revelation. But Joffe winds up wasting much of this tension and intrigue with an oddly definitive ending. In a film filled with questions, doubts and uncertainties, it feels completely out of place and emotionally untrue.

Joffe's cast, at least, is unreservedly excellent. Kidman delivers her most fascinating performance in ages, one that's equal parts vulnerable and strong. Her Christine is very much a victim of her circumstances - and possibly her husband - but Kidman skilfully imbues her with a steely determination to reclaim her life and identity against very poor odds. Firth, too, is fantastic, shading both light and darkness into his trademark charm - enough to make us believe that he's the kind of man who could love and/or betray Christine with all of his heart.

It's a shame, then, that the final frames of the film don't live up to its promise or potential. Joffe has hit upon something truly unnerving with his premise: Christine's condition provides the ideal backdrop for either the perfect crime, or a love story for the ages. Before I Go To Sleep quite effectively teeters between the two extremes, as does Christine, but ultimately fails to follow through when the true depths of its darkness are revealed.

Overview: Clever, emotional, Kidman in her 40's is a totally different actress (hopefully she'll get a role that will become a classic).

If you've seen 50 First Dates and Momento then you will have this movie pretty much figured out in the first 15 minutes or so. However that said it still manages to leave you just as uncertain about what's going on along with Kidman's character until the reveal. Careful observation will give you the clues though. The plot is clever and as you'd expect Colin Firth acts superbly and Mark Strong is also very good as the Doctor. As for Nicole Kidman I must confess age has done her wonders, gone is that teenage look that may have prevented here being taken seriously for "heavy" parts. The Others was a bit wooden (although the character did require that in fairness), Australia would have benefited from Nicole's more mature look. She is excellent, pulling you in to her confusion and roller coaster of emotions she goes through with each day and set of new facts she finds out. I really enjoyed this movie and would highly recommend it to anyone who likes a clever thriller without the pointless need for tons of special effects.

DON'T read spoilers, they really will ruin the film for you.

In 1995, there was a movie called "While You Were Sleeping", a romantic vehicle for Sandra Bullock, but this 2014 similarly-titled work is very different: a thriller with Nicole Kidman in the central role as Christine, a woman who suffered a serious assault years ago and now forgets everything each time she sleeps. Two men are trying to help her, husband Ben (Colin Firth) and therapist Dr Nash (Mark Strong). Like most standard thrillers, we find that our assessments of the principals swing back and forth before 'the big reveal'.

There is a sub-genre of movies involving limited memory - think "Blink", "The Bourne Identity" or "50 First Dates" to name just a few - and "Before I Go To Sleep" is not the best of them (that would be "Memento") but, if one does not think too much about the implausible narrative, this is entertaining enough, helped by good source material (the best-selling novel by S J Watson) and the solid acting (Kidman with a good English accent, Firth not as straighforwardly charming as he is usually, Strong not as as unremittingly threatening as he is so often).

The film opens with a woman, played by Nicole Kidman, waking up in bed with a man. She seems disconcerted and confused. Entering the bathroom, she encounters photos of the two of them. Leaving the bathroom, she sees the man, played by Colin Firth, who is now sitting on the bed. He tells her that they are married but that she had an accident, and that she can no longer retain memories more than a day. Mr Firth then goes off to work, and Miss Kidman is then phoned by a man, played by Mark Strong, who says he is her doctor, helping her to get her memory back. He instructs her to find a hidden camera, which she does, and finds that she has filmed herself, to leave messages to herself.

These are the opening scenes of the film which are also in the trailers too. Thus the film looked exciting and worth going to see. Which it is. The source material for the film is a 2011 novel by SJ Watson. This debut novel may be applauded, as may the film, however both are really not that original.

It may be recalled that in 'Total Recall' (1990), a humble construction-worker, played by Arnold Schwarzenegger, has a wife, played by Sharon Stone. A little bored, Mr Schwarzenegger goes on a mental holiday as a secret-agent, only to find that he really is a secret-agent. He finds this out, when escaping the bad guys, he finds a film of himself, telling himself, that very thing.

It may also be remembered that in Memento (2000), Guy Pearce also played a guy with no memory. This memorable, and remarkable, film, starts at the end, and the whole story is told in reverse as Guy Pearce, helped by Joe Pantoliano, tries to find out who killed his wife, using tattoos to keep notes.

Thus, 'Before I Go To Sleep' is not based on an original idea, but rather the concept is very familiar to those who have seen 'Total Recall' and 'Memento'. However, this does not make this a bad film, far from it. Whilst not original, the film is a little different from the other two films. They were more action movies than this one, which concentrates on the relationships.

The acting is superb throughout the film. Miss Kidman captures the emotions perfectly. We have no doubt that each day she wakes up in a strange bed with a strange man. Mr Firth too, acts well as the loving husband who has to explain everything to her, every day. Perhaps of the two, Mr Firth has perhaps the more demanding role. He has to show both exasperation and love, and he conveys his range of emotions well. Miss Kidman has perhaps a slightly easier role to play, that of the innocent woman, not understanding, or knowing who to trust. The ever reliable Mark Strong, playing the doctor, also gives a very subtle and ambiguous performance.

Rowan Joffe is the Director, and also wrote the screenplay. He has done very well to get very emotional and realistic performances from his trio of central characters, as well as from the supporting cast. Mr Joffe maintains the emotion, mystery, and tension, throughout the film. At times, you could be forgiven for thinking, that you were watching a film by that master, Mr Alfred Hitchcock. Parts of the film can easily be compared so, stylistically. However there are also many emotional kitchen-sink-style domestic scenes, all captured well.

If you like adult-themed mysteries and thrillers which deal with relationships, as well as messing with the mind, then this is the film for you.

Good film. 9/10.

"Tonight as I sleep, my mind will erase everything I know today"; The simple yet satisfying plot-line of this movie as spelled out by our lead protagonist in the opening scene is enough to draw anyone into this wonderful thrill ride of a film. Such a story-line sees the aforementioned central character (played by Nicole Kidman) slowly put back together the extremely complex puzzle that is her memory of the last 14 years, lost after an 'accident' involving a mystery perpetrator.

The plot, although clearly ludicrous when heard, somehow works remarkably well when experienced on screen. This is primarily down to the breakneck pace of the movie, never allowing audience members to get bored or have enough time to ponder the numerous plot holes noticed after the final credits. Not that this matters of course, as BIGTS is a picture to be enjoyed in the moment and at surface level.

Another of the film's major assets is the brilliant performances from the central three characters. Kidman is back on form, exasperating any memory of a certain picture that occurred sometime in the previous 14 years; Firth is excellent also as Ben, with Strong matching him in equal measures on levels of sinister and downright frightening unpredictability. Not only is such fantastic acting a joy to watch, it is another factor in helping the plot-line to be accepted without question by audiences who might think twice if only they weren't having so much fun.

As entertaining as the picture is, this isn't groundbreaking original stuff here, nor is it something that is terribly deep in content. However if you want to spend 90 odd minutes utilizing only the first third of your seat, then you're in for a treat.