Grade: B

Verdict: A "Risky Business" retread that's completely ludicrous but so sexy, silly and fun you won't mind at all.

The fetching comedy "The Girl Next Door" is a teetering bit of risky business.

It's got too much naked skin and too big and fat of an R rating to be a bona fide teen movie. But set in a high school it is, with an unfathomable plot about an officious student council president who, one day, discovers a curvy porn star has moved in next door. To boot, the curtains on her bedroom window are wide open.

We should all be so lucky.

Of course, the porn star with a heart of gold (and a stuffed teddy bear) falls for our nerd. They date. They kiss. And before long the senior prom looks like it's a backdrop for a new porn venture. But much of the film's lascivious nature is, at its very soul, a tease. Did we forget to say this was a feel-good Hollywood studio movie?

Also true is that our gal's got equally curvy co-workers she eventually calls up to be escorts for her neighbor's even more nerdy pals.

It's all too unbelievable, but also quite funny.

"Girl Next Door" is sexy, silly, sappy and often just plain likeable. The movie's blessed with a good, sometimes even wicked, script and two fine young stars -- handsome Emile Hirsch ("The Dangerous Lives of Altar Boys") and drop-dead gorgeous Elisha Cuthbert (TV's "24'). They are likely the most beautiful twosome you've seen since, well, "Risky Business" propelled the screen careers of Tom Cruise and Rebecca DeMornay.

A clear-eyed cousin of sorts to Cruise's 1983 top-10 box-office film (then it was prostitution, now its hard-core porn), "Girl Next Door" has sexual chemistry to burn. It doesn't even attempt to create a fresh screen milieu. When Cuthbert first strips, in slo-mo of course, the film's soundtrack pulsates with the same kind of entrancing tonal reverberations that audiences heard when Cruise and DeMornay immortalized their film with a steamy scene inside a Chicago subway car.

Oh, and later the deed that was done on that previous film's subway has been transported in "Girl Next Door" to a stretch limo after Hirsch and Cuthbert depart the senior prom.

We should all be so lucky.

This is a movie as preposterous as "Pretty Woman" and almost as watchable.

Timothy Olyphant ("Scream 2" and HBO's "Deadwood") shows up as a porn director looking like he's channeling the moussed fashionata of "Blade" villain Stephen Dorff. His character is normally a paper-thin villain in this kind of film, but the script gives him extra bite, making him honestly friendly one moment and creepily edgy the next.

Hirsch also has two geeky friends who'll make you laugh and a high school full of outrageous cliques. As one of the sports jocks shouts in a school meeting about the prom, "Security's going to be tight, so everybody get wasted before you show up!"

Ultimately, the film does pose the question, "What is moral fiber?"

The answer is honest, forthright and one that proves a nerd can wind up with the girl.

We should all be so lucky.