This film is one of those cross-genre movies that must drive marketing people nuts. Part murder mystery, part erotic suspense thriller, part black comedy, the marketing people took one look at this, saw Steve Martin, and called it comedic. Really, it's more ironic than comedic. The situations in which people find themselves, from Laura Dern's OCD fiancee to Steve Martin's repressed dentist caught up in a spiraling web of deceit are definitely not funny in the traditional sense, and I am sure that is what put many people off about the film.
Despite the unsavory elements of the story and only average acting from otherwise good actors, the story holds the audience's interest, subtlely foreshadowing the climax, which unfortunately "pays off" all too quickly after the amount of work that goes into setting it up.
This, plus the aforementioned average acting and dark storyline are the primary reasons that this movie is usually found in the bargain bin. Still, Helena Bonham Carter is definitely worth watching as a drug addict, abused by her incestuous brother. Some of the character's dress and actions are vaguely reminiscent of her portrayal of Marla Singer in Fight Club, and she remains sufficiently tortured throughout the film to add a slightly deeper layer to the film.
Not for the squeamish (or dentist averse), the film has an ironic but "happy" ending that leaves the viewer a bit unsettled, mainly because it ends a little too cleanly. Not Steve Martin's best work, by far, but certainly an amusing diversion.