What comes first for a writer -- motivation or inspiration? In Swimming Pool, a psychological thriller about an author of British crime novels, it's not easy to tell. Tired of writing her popular "Inspector Dorwell" stories and upset with her publisher for his lack of encouragement to try something new, she accepts an offer to spend time at the publisher's secluded villa in France. Maybe a change of place will provide inspiration for a different type of book.

But, as the old saying goes, no matter where you go -- there you are. So, despite the beauty of her borrowed surroundings, Sarah Morton (Charlotte Rampling) continues being an uptight, grumpy scribe. At least until nymphet Julie (Ludivine Sagnier), the publisher's daughter, arrives for an unexpected stay. This free-wheeling, sexy young girl becomes the catalyst for a dramatic change in Sarah's personality and writing. When a fatality near the villa's swimming pool bonds the two women together, Sarah finds herself more in tune with Inspector Dorwell's suspects than with the hero of her crime novels.

It's difficult to put into words my reactions to Rampling's (The Verdict) amazing work in this film. Movies about authors and the writing process usually lack cinematic excitement. Not this one -- primarily because of the elegant way Rampling manages to project Sarah's changing moods and attitudes. Consider a simple phone conversation in which she registers deep disappointment with her publisher (Charles Dance of Gosford Park) at hearing he won't be coming to see her. It takes only a tiny, silent movement of her lips to make viewers aware of Sarah's frustration with the neglectful publisher. Throughout the film, Rampling's expressive face fascinated me by revealing exquisite details about Sarah's feelings during her metamorphosis.

Unusual cinematography by Yorick Le Saux (Eager Bodies) also drew me into the author's changing world. At times, he photographs Sarah reflected in mirrors and windowpanes -- perhaps hinting at the film's artistic, enigmatic ending. And Director Francois Ozon (8 Women) teases the story along with just enough suspense to make me curious about how everything would turn out.   

Although no match for Rampling in the acting department, Sagnier (8 Women) exudes sensuality and youthful energy as the overly outgoing Julie. (Surprisingly, it's Rampling who has the most graphic nude scene here.) The rising young French actress, soon to be seen as Tinker Bell in the upcoming Peter Pan, portrays her mostly unsympathetic character with convincing focus. More than once, I found myself wanting to shake some sense into her.

My only complaint about Swimming Pool is a selfish one. It involves the film's concept that a successful author of British crime novels would want to disappoint her readers by writing something else. As an avid Martha Grimes fan, I hope she doesn't see this movie. She might decide to write another book without Superintendent Richard Jury as her main character, and I'd have to wait too long for her next book about my favorite detective.

My apologies for digressing. You're probably wondering what happens to Sarah after she leaves the French villa and how much she discloses to her arrogant publisher. No spoilers are allowed here, but I'll give you an important clue --  writing well is the best revenge.

(Released by Focus Features and rated "R" for strong sexual content,  nudity, language, some violence and drug use.)