A pretty girl sits on a couch reading, her face spotted with zit cream, her dog stretched out on the floor at her feet. She gets up, chain locks the door, and turns to look at her pet, splayed out on his back, his genitalia in full view. The next thing we know, the girl is running for mouthwash to the accompaniment of one of the best voice-overed opening lines in recent cinema history: "My name is Amy, and yes, in college, I blew my dog."

Bobcat Goldthwait's Stay isn't about bestiality as a fetish or a lifestyle – Amy's, um, indiscretion was a one-time thing, borne from boredom and unsatisfactory at best – but it uses the ultimate taboo as a male adolescent-approved in to talk about the role of honesty in contemporary relationships. Amy has kept this secret for years, but when her boyfriend John asks her to marry him, she starts to wonder if there's room for such a secret in a marriage. Weighing the advice of her co-worker and her mother (both of whom have their own sexual secrets), Amy must decide whether or not to break down and let the dog out of the bag. Her eventual decision backfires, and Amy finds herself hated by the very people she was trying to please. Matters are made worse by the interference of Amy's meth-addled brother Doug, whose casual hatred is at once racially charged (he didn't lose his job; it was taken by "the kikes and the niggers and their quotas'") and indiscriminate. Things are looking dark indeed, until a family tragedy touches off an unexpected, and unexpectedly satisfying, resolution to Amy's moral quandary.

Melinda Page Hamilton plays Amy, and it's a breakout performance if I've ever seen one. The actress is best known for playing a nun on Desperate Housewives, which gives her work here as the sexually voracious but morally conflicted Amy a nice little tweak. Hamilton, with her thin blonde hair and sapphire blue eyes and skin so pale it's almost clear, looks a lot like Renee Zellweger might look – if she was pretty, radiant and smart as a whip. Hamilton accomplishes things here with a blank stare that most contemporary actresses her age need a page of monologue to convey.

The press screening on Sunday morning started out packed, but journalists trickled out throughout. The 75% of the audience that stayed seemed to enjoy Stay quite a bit, although the experience was undeniably hampered by a crap digital projection that painted orange noise on almost every shot of Hamilton's otherwise stunning face.

Word around town has it that the film's "edgy" content is scaring off buyers. The very fact that the plot hinges on dog fellatio aside, I wish the suits weren't so afraid. Stay is an adult comedy about a girl who blew her dog and lived to regret it, but it's also an incredibly sweet and insightful adult comedy about a girl who blew her dog and lived to regret it. Bobcat Goldthwait has somehow produced a script that understands something about the gulf between what men claim they want from women, and the way they behave when we give it to them. Its careful balance of old-Hollywood melodrama (the score is hilarious, by turns silent film tragic and 50s soap opera subtle) and college humor charges the film with a bizarre kind of energy that I'm not sure I've ever seen on screen. Stay deserves to be seen.

Others on Stay: The Hollywood Reporter's Duane Byrge calls it a "carnal, crazy and, most amazingly, heartwarming love story," while Todd McCarthy at Variety feels the film "far exceeds the limits of how far a one-joke comedy can be extended," and describes a theatrical run as "a real long shot."