You never know how or why amnesia will strike in a Hollywood movie. In the case of Christine Lucas, Nicole Kidman’s character in the upcoming thriller Before I Go to Sleep, the lingering effects of a brutal assault ten years ago leave her unable to hold onto new memories for longer than a day—unfortunate, since there seems to be a rather high-stakes conspiracy unfolding around her.

Written and directed by 28 Days Later screenwriter Rowan Joffe (and based on S.J. Watson’s eponymous 2011 book), the film stars Colin Firth as Christine’s husband and Mark Strong as the doctor who’s working to help restore her memory, although neither seems to be quite who they claim. Between Christine’s whispered video diary entries, the implication that secrets are being piled on top of secrets, and a shot of Kidman standing nude before what seems to be a “conspiracy web” wall, the film seems ripe for paranoia and surprise twists.

Before I Go to Sleep is slated for a September 12 release. Hit the jump for a preview.