Bobcat Goldthwait's Sleeping Dogs Lie premiered at Sundance as Stay. Both titles are acceptable double-entendres on the film's starting point -- giving a dog a blow-job -- and throw in another resonance for good measure, but the old title was better. Sleeping Dogs Lie tells us not to blow dogs while acknowledging the cliche about dormant problems better left undisturbed, but Stay isn't just a naughty command to a dog to hold still; it's the kind of desperate imperative spat out in a relationship's last legs. The new title is cheekier, but the old one gives a better sense of what the movie's actually like: For all its ostensible shock value (the main selling point), Sleeping Dogs Lie is in fact mostly shockingly sincere.

Amy (Melinda Page Hamilton) is a self-described nice girl, a college graduate who teaches elementary school kids -- "and yes," she admits in exasperated introductory voice-over, "in college I blew a dog." Why she can't say -- a stupid whim that, once committed, was regretted and buried. But when her fiance John (Bryce Johnson), in their drift to marriage, insists on mutually sharing their worst secrets, the relationship degenerates into a nervy game of truth-or-dare. No matter what John admits to, Amy knows he'll never beat her, and in that inequality lies the crux of her dilemma.

Because its central joke can sustain roughly five minutes, Sleeping Dogs Lie quickly detours from abortive sex farce to awkward meet-the-folks comedy as Amy and John confront Amy's relatively strict religious parents; her buried secret means they quickly have bigger problems to confront than hiding her smoking habit. For much of its brief running time, the film veers awkwardly between gross-out comedy, family farce and isolated patches of seriousness.

And then it turns completely serious. Conversations between the couple turn from funny-awkward to straight dramatic hysteria, and the spectre of familial death hovers. As befits a man who has fallen from the dizzying heights of sustaining the middle legs of the Police Academy franchise to directing Jimmy Kimmel Live, Goldthwait's film is not only barely competent visually (ugly video shots of blandly pleasing actors in two-shots; scene transitions signaled by establishing shots set to jangly music reminiscent of sitcoms), but prone to narrative collapse between the first half's relatively delicate comedy and the aggresively foreshadowed confrontations guiding the second half.

Yet for all its technical inadequacies -- and despite the fact that the bargain-package cast is as generically clean-cut as can be for a story of major emotional upheaval -- Sleeping Dogs Lie works because Goldthwait's world view is far ahead of the flat romantic comedy he sometimes threatens to slip into. Honesty, the film concludes, is best applied judiciously: All relationships thrive because of -- not despite -- selective falsehoods and omissions of truth. That Goldthwait manages to arrive at such a complex resolution within an unholy hybrid of two of film's least reliable sub-genres -- the gross-out comedy and the romantic comedy -- makes his film peculiarly riveting. Even when it collapses into rote sentiment, it's hard not to both take it at face value and wish that the pragmatic worldview was more elegantly expressed. The ending looks for all the world like a conventional chick-flick resolution, which neither leavens the emotional weight or brings anything new.

Even with its compromises, Sleeping Dogs Lie still feels more unnerving than, say, any of the Farrelly Brothers' overrated work, which (nowadays, anyway) treads a similar path between unobjectionable comedy and inclusive humanism. Flawed as it is, Sleeping Dogs Lie upsets the traditional view that a sleeping Bobcat -- once a comedian as reviled as Pauly Shore or Carrot Top -- should be let alone.