"Chloe" wants to be an erotic thriller.

At least, that's what I think it aims to be. It's difficult to know for sure, what with its eroticism mired in fussy pretensions and its suspense mainly stemming from how the moviemakers will possibly resolve the silliness.

Scheduled to open Friday, the movie is a serious disappointment from Atom Egoyan, the director behind such critically acclaimed fare as 1994's "Exotica" and 1997's "The Sweet Hereafter." Those films explored sexual and moral complexities, but "Chloe" is just a muddle.

The storyline follows an affluent couple whose marriage has grown as chilly as the film's Toronto setting.

David Stewart (Liam Neeson, "Taken") is a college music professor who's particularly chummy with his female students. His wife, Catherine (Julianne Moore, "A Single Man"), is a successful gynecologist who suspects her husband is up to more than innocent flirtation.

Her fears appear to be confirmed when she puts on a surprise birthday party for him. David, who has been in New York for a lecture, misses his flight back home. The next morning, Catherine finds an incriminating text and photo on his mobile phone.

Shortly thereafter, a chance meeting in a restaurant bathroom introduces Catherine to Chloe (Amanda Seyfried, "Jennifer's Body"), a young, mysterious prostitute. In the first of several tortured contrivances, Catherine hires the comely call girl to test David's fidelity.

Chloe takes the assignment and dutifully reports back that he was easy to seduce. The revelation devastates Catherine, but "” this being the kind of picture destined for late-night Cinemax "” she also finds it strangely arousing. Catherine directs Chloe to continue with the trysts and report on them in lurid detail. It becomes clear that the relationship between Chloe and Catherine is decidedly more complicated "” and intimate "” than that of temptress and victimized wife.

The notion of parallel affairs"” one carnal, the other verbal and vicarious "” is an intriguing one, and, for a while, "Chloe" is interesting, despite its own suffocating ponderousness.

But then a curious thing happens: Egoyan and screenwriter Erin Cressida Wilson ("Secretary"), in adapting the 2003 French-language film "Nathalie," plunge into eye-rolling absurdity.

Fictitious characters, by definition, can be subject to all kinds of manipulation that strain credibility, but "Chloe" does more stretching than an aerobics class. Chloe herself, despite Seyfried's gameness for displaying skin, never feels like a flesh-and-blood person. She is a plot device, pure and simple, engineered solely to move along twists that defy reason.

Not that there isn't some crass fun to be had in this mess. The final third is so outrageous, so risible, as to approach high camp. What else can you say about a flick in which a woman literally has an orgasm "” a shoegasm, if you will "” by glimpsing a closet full of footwear? That's funny stuff, but you have the impression that the filmmakers don't get their own joke. "”Phil Bacharach