"The Door in the Floor," a tragicomic melodrama set amid the hedgerows and hydrangeas of East Hampton's upper reaches, stars Kim Basinger and Jeff Bridges as a couple coping -- or not -- with unspeakable loss. Like such bourgeois gothic predecessors as "In the Bedroom" and "Ordinary People," Tod Williams's film features people suffering attractively in well-appointed rooms; unlike those two much better films, "The Door in the Floor" doesn't deepen as it progresses but becomes flimsier and more trivial, finally succumbing to an awkwardly executed tonal shift.

As a showcase for two of the most attractive middle-aged actors around, it half-works. Bridges, as usual, delivers an expansive, unself-conscious performance, this time as an affected, self-involved artist. Basinger, for her part, projects just the right combination of weariness and physical ripeness to play a role that demands both grief and allure, but it's in the service of an insipid exercise. Her job is to mourn beautifully, and that's all she does.

Bridges and Basinger play Ted and Marion Cole, a children's book author and his wife who live with their 4-year-old daughter in a gorgeous waterfront house. But it wouldn't be a movie if anything so photogenic lived up to such seductive surface charms: Marion is miserable, haunted by family tragedy and finally tired of Ted's increasingly perverse philandering. On the verge of their breakup, Ted hires an assistant for the summer, an Exeter student named Eddie (Jon Foster, resembling a young Matthew Modine), who proceeds to change Ted's commas to colons with abashed enthusiasm.

Although Ted and Marion separate just as Eddie arrives on the scene, the teenager and the older woman eventually gravitate toward each other, and as their relationship progresses, "The Door in the Floor" becomes something of a "Summer of '42" for the 21st century. The affair is both anticipated and echoed by Ted's own children's stories, all of which have a dark, psychoanalytic edge.

The title of the movie is taken from one of Ted's books, about a recalcitrant fetus and the anxieties, desires and self-destructive impulses shared by even the most innocent among us. The author of this perverse allegory is himself a ridiculous figure, a voracious, arrogant epicure who says things like, "I'm just an entertainer of children and I like to draw" while giving his hand a studied waggle.

Williams, who has adapted "The Door in the Floor" from the John Irving novel "A Widow for One Year," has wisely chosen to use only the first third of that book for his inspiration, avoiding the compression and compromise that befall so many book-to-film projects. This is a carefully conceived, thoughtfully orchestrated effort in taste and restraint that ultimately is too restrained and tasteful: For all the film's painstaking attention to atmospheric detail, the stakes don't seem very high, even when Eddie makes his grand climactic gesture. Indeed, perhaps the film's most compelling character -- certainly the one played in its bravest performance -- is a shadowy figure named Mrs. Vaughn, Ted's latest victim of seduction and abandonment. Played by Mimi Rogers, she truly seems to register the monstrous things going on around her, even if it's ultimately played for laughs. She's the only one who seems to possess recognizable emotions in the midst of otherwise strange, beautiful but sterile hothouse flowers.

The Door in the Floor (111 minutes, at area theaters) is rated R for sexuality, graphic images and language.

A wife (Kim Basinger) separated from her cheating husband, a children's book author, starts an affair with a college student hired as his assistant. Jeff Bridges, left, plays the arrogant writer; Elle Fanning is the couple's child.