In "The Private Lives of Pippa Lee" Alan Arkin plays Pippa's husband, Herb, a semiretired publisher who has found a promising new novel with crossover appeal.

"It's highbrow for lowbrows, lowbrow for highbrows," he says, an assessment that nicely fits "Pippa Lee," as well. It's the midwinter film equivalent of a summertime beach book, an engaging time-waster with some passages you savor and others you wish you could riffle through quickly.

Robin Wright Penn plays Pippa, a sweet but aimless enigmatic beauty who has moved through life as a pawn in other people's games. She has a life that's in some ways enviable, living in comfort and moving in a circle of articulate, handsome, appreciative friends. On closer examination, though, her privileged routine of dinner parties and light conversation leaves her with a gnawing sense of incompleteness. Even as she enters her 50s, Pippa is much like young Pip in "Great Expectations," a storm-tossed child of fortune dependent on the goodwill of others.

Herb is much older and in unstable health, obliging them to move to an affluent retirement community. Her friends have selfish personal agendas that undermine her, and when Pippa takes up the kitchen blowtorch to caramelize the tops of their crème brûlée you get the sense that she's just one step away from arson.

How she came to be trapped in this golden cage is the movie's story. Judged always in terms of her spectacular looks (she's played in childhood by Madeline McNulty and as a young adult by Blake Lively, both knockouts), Pippa grows up hesitant and uncertain, never getting the practice necessary to build up her independence. Mommy -- a diet-pill addict played with feral energy by Maria Bello -- dresses her up like a Barbie.

She runs off to live with bohemian Aunt Trish (Robin Weigert, warmly appealing), but the story remains the same. Trish's lover, edgy, artsy Kat (a manic Julianne Moore), recruits Pippa to star in lesbian fetish photo sessions behind Trish's back; she passively agrees and gets pleasure from it. When Pippa wanders into New York's upscale art scene as a stunning free spirit, she catches Herb's eye. For all his sensitivity, maturity and insight, he uses Pippa to his own ends, the perfect hostess and helpmate for his declining years.

Pippa feels surges of guilt for her wobbly relationships, though how a child could have negotiated the rapids of so many abusive personalities is an open question. Writer/director Rebecca Miller stacks the deck in her heroine's favor, surrounding her with terribly nice people who gradually reveal devious and greedy personalities.

"Pippa" boasts a stellar cast in Keanu Reeves, Winona Ryder, Monica Bellucci and even Princeton professor Cornel West. There is a generous serving of story as poor, put-upon Pippa reminisces about her past and wrestles with her present challenges, which include the attentions of a footloose young convenience store clerk and troubling mental health crises. But the movie has the busy-aimless feeling of a cocktail party rather than a rigorously constructed drama. Interesting people drift through, anecdotes are shared, attention shifts here and there, and abruptly it's time to go.