I have already read the book by SJ Watson, but despite this I still found the film quite good but not as good as the book.
Every time 40 year Christine (Nicole Kidman) goes to sleep she loses her entire memory. When she wakes up she asks the man lying next to her (Colin Firth) who he is. I’m Ben your husband, he replies. Each morning Dr Nash (Mark Strong) phones Christine and reminds her that she keeps a video diary recording what she has learned about herself each day. She finds inconsistencies between her diary entries and what Ben tells.
The book is more intense in that it is written from Christine’s point of view, which the film can only do in the video diary playback scenes. There was a lot of repetition in the book as Christine wakes up each morning and goes through the same routine. This was shortened in the film with just the phone call from Dr Nash to indicate a new day.
The tension does build up in the film but the second half of the book is really scary and the climax is covered better in the book. I’d give the film 3 stars.