Less is more in Francois Ozon's marvelous mystery which slyly finds resolution by not resolving itself. It's a beguiling, interiorized and spare piece that's grounded with an extraordinary performance by Charlotte Rampling. Rampling, if you recall, is the '60s/'70s British screen siren whose svelte presence and cobra eyes graced The Night Porter and Woody Allen's best movie, Stardust Memories and who, after a long stretch raising children and taking only a few small roles - Wings of the Dove for one - has returned to movies (she's a marvel in Jonathan Nossiter's Signs & Wonders) with a vengeance.

Here she's Marie, a fiftyish college professor in Paris, teaching the novellas of Virginia Woolf and quoting The Waves to her class with prophetic haunting. Marie is relishing the upcoming summer holiday and she and her sloth-like, hulking husband, Jean (Bruno Cremer), are on their way to Jean's family beach house. The couple arrive and ready the house, eat spaghetti, drink an old bottle of wine and discuss their plans for their first day of vacation. 

Next morning they're on the way to the beach. Jean says he's going for a swim. Marie replies she's going to read a paperback. He rubs lotion on her back and ambles to the water. She fades into a deep, sun-stoked sleep. When she awakes, Jean is nowhere to be found. Marie runs up and down the beach, asking a couple if they've seen her husband. No one has. She races to the shore police and an investigation is begun. But Jean has disappeared. Has he drowned - or has he plotted the abandonment and left her?

After the film returns to Paris, Marie seems at peace with her solitary life. But we begin to see that Jean has never left her. She prepares meals, talks to her husband, greets him when she returns from dinner at a colleague's home and accepts the advances of a businessman who is smitten with her. To the world's eyes she is functioning perfectly after her loss. But Marie resolutely rejects any one or thing that appears final as far as Jean's absence.  And that is the element that propels Under the Sand over its kin. This is no sexual-hysteria piece like Roman Polanski's Repulsion, in which Catherine Deneuve becomes murderously unbalanced. Indeed, the fantasy Marie fuels is preferential, almost a life choice to Marie, even if her friends think otherwise and Jean is only a manifestation of her denial.

Slowly Ozon turns this lean storyline into a complexity of middle-age crisis. Marie's reading of Woolf - "What have I lost? I have lost my youth" - becomes key to this astute film. More amazingly, Ozon, only in his 30's, delves into the corners of a middle-age woman's mind, grasping her fear of the future and that which is unknown.