Director Gary Winik's new film "Tadpole" can be accurately summed up in one volley of dialogue. "It's all very 'The Graduate'," says 15-year-old Oscar's stepmother when she discovers he's slept with her 40-something best friend. "Except that Oscar hasn't graduated!" replies the boy's dad.

Oscar Grubman (Aaron Stanford) is back in uptown Manhattan from his upstate New York private high school to spend Thanksgiving with his father Stanley (John Ritter), a Columbia history professor, and stepmother Eve (Sigourney Weaver). On the train back, he runs into a schoolmate -- Miranda Spear (Kate Mara) -- harboring an obvious crush. But the sensitive, extremely intelligent and Voltaire-obsessed Oscar loves another woman ... his stepmother!

After the holiday dinner, Stanley wants Oscar to walk home Daphne (Alicia Van Couvering), the daughter of another professor. Oscar's not interested, though, and tosses her into a cab and heads to a bar. While stumbling home, he falls into the bed of Eve's life-long friend Diane (Bebe Neuwirth).

Now, Oscar's terrified not only that Diane's insignificant other, Phil (Adam LeFevre), will find out, but also that Eve will. Thus ensues endless laughter as Diane appears ready to burst and tell all and Oscar does what he can to stop her.

Regardless, it all comes out and Oscar learns some valuable lessons, etc., etc. In the meantime, there's laughs -- and Voltaire quotes -- galore in this intelligent romantic coming-of-age comedy.

At a mere 78 minutes long and wonderfully witty, "Tadpole" flies past. But it's also got a sad, unrequited adolescent love component. This is to say nothing of the questions raised about why it appears completely OK for a 45-year-old woman to sleep with a 15-year-old boy -- and then introduce him to her similarly lonely friends. Obviously, the film would certainly have a different feel, and plot, if the genders were reversed. (Although in "Pumpkin," another new film, one college-age character is expelled from school for sleeping with a 15-year-old boy -- perhaps this is a new trend).

"Tadpole" opens Fri., Aug. 23 at Landmark's Oriental Theatre.