Meanwhile, Christine gets help each day on the sly from Dr. Mike Nasch (MARK STRONG), a psychiatrist who finds her case fascinating. He tells her to start keeping a daily video journal that she can watch each morning after her husband leaves for work that will give her an update on all of the things she learned from the previous day. He calls her each morning, introduces himself, then tells her to retrieve the camera from her secret hiding place in the house. But he has a brooding, mysterious way about him, and he is sometimes too quick with a psychological explanation for nearly everything Christine experiences.

Christine's memory is further tested when she becomes aware of a best friend named Claire (ANNE-MARIE DUFF), who has information that directly contradicts what Ben has been telling her. Their meeting points Christine in new directions as she struggles to figure out what's true, what's false, and what might place her in harm's way once again.

And while I'm thinking of it, I really hesitated to use the word "thriller" in that opening paragraph to categorize "Before I Go to Sleep." There are very few of what most people would call "thrills" in this flick. I mean, is it a thrill to watch Nicole Kidman get beat to a bloody pulp? Not for me. Sure, it's always a thrill to watch her walk through a scene stark naked. I've been enjoying that since her "Billy Bathgate" days in the early '90s. But that little thrill takes place here in the film's first two minutes. Nary a bare buns is visible again for the other 90 minutes.

What we're left with is a grave, hesitant mystery about a 40-year-old amnesiac woman who wakes up every morning thinking she is 25, looking in the mirror, and wondering, "Whoa? When did I get a nip and a tuck?!" Actually, she wonders, "Where am I?" "What's my name?" and "Who's that man is in my bed?" The answers are: She's home. Her name is Christine. And that's her husband (Colin Firth), who has to explain to her every morning before coffee and bagels that she has a rare and severe form of amnesia known as DrewBarrymoria in which she wakes up each day with no memory of the previous day or really anything since getting in a bad car accident years later.

When the hubby leaves for work, though, Christine gets a call from a mysterious Dr. Nasch (a strong Mark Strong), who tells her each day to go to a secret drawer where she will find a camera and to hit the "Play" button. On the camera are videos that Christine has been making as she tries to piece her past together and regain her memory. One thing is clear very soon. Her husband has not been telling her the truth about a number of things -- chiefly that her memory loss is due not to a vehicle crash, but to a brutal assault four years earlier that left her nearly dead. Is he sparing her certain details of her past because they are too traumatic? Or is he hiding something more sinister?

"Before I Go to Sleep" should have more fun trying to answer these questions. But the whole thing is all played in one tone, somber. Say what you want about "Gone Girl," a similar puzzle-box of a film that also centers on a warped marriage and is based on a best-selling novel. But that had the sense to be good trashy fun even when the storyline got lurid and even grim in spots. There's no such sense of play in "Sleep."

And the actors are almost too good for this material. If you're going to play the whole thing deadly straight, you actually need cheesy C-listers like grown-up "Saved by the Bell" or "Melrose Place" stars to play these roles. Where have you gone Tiffani Amber-Thiessen and Grant Show when good Hollywood trash needs you so badly?! At the very least, they wouldn't have made this snoozefest. I give it a 4 out of 10. (T. Durgin)