He seems like deliverance itself on a rainy day. There she is in her English school uniform, getting soaked to the skin. He slowly pulls up in a plush-looking maroon car of a sort she’s never seen before. “It’s a Bristol,” he says. There were “not very many of them made,” he explains.

And drives her home.

And almost wrecks her life.

It’s 1961. What people call “the ’60s” hasn’t quite happened yet, but is in the wings.

To all who know her, Jenny, 16, is Oxford material through and through. She plays the cello, gets soaring grades in almost everything and, in private, sings along with Juliette Greco records and yearns to go to Paris, to shed bourgeois boredom, smoke cigarettes in cafes and be an existentialiste.

There’s a world of culture and wit and fascination and meaning out there. But all she sees in her world are schoolgirls who wear the same uniform she does and some teachers who seem terminally closed off from excitement and a family that can always be counted on to say the dreariest things possible at every moment. (Dad, among other things, is a xenophobe and a not-so-genteel anti-Semite, along with being a fellow who’s so unmusical and so provincial that he has no idea even how to get to a place where an interesting concert is being held.)

And then this gentle, soft-spoken cultured older man drives into her life in his maroon Bristol saloon. He takes her to chamber music concerts, introduces her to men who drink languidly and women whose decolletage bursts decorously out of low-cut dresses.

He can even charm her charmless father.

Her future at Oxford — to which she hasn’t even applied yet — begins to take a beating.

And then comes the proposal of marriage.

As played by Peter Sarsgaard, the seductive older man seems the very antithesis of the horndog seducer with a taste for jailbait. He’s a kind, sensitive older man with all the charm and manners she knew existed in the world, even though she had never seen much of them herself.

To put it another way entirely, he’s played onscreen by Peter Sarsgaard, not George Clooney or Matt Damon or the B-list equivalent.

There are a few distant early warnings on the radar screen. He and his BFF do seem to think it’s a lark to steal valuable antique maps right out from under a little old lady’s eyes. And their livelihood seems to be a bit more mysteriously defined than it ought to be.

But it’s 1961 and gender roles were more rigid. A lot fewer questions were asked on date night.

He seems to offer everything in life she has always wanted — even the trips to Paris.

And, of course, the carnal awakening, ever-so-gentle defloration and all.

To be sure “An Education” is an old story, but there are two things here that make the movie stand out and become almost completely irresistible — one new and one not-so-new.

The new one is actress Carey Mulligan as Jenny. She has, like Katie Holmes, a kind of sweet schoolgirl beauty that can change into something far more sophisticated without strain. Unlike Holmes, she has a kind of ever-present, self-possessed intelligence.

The not-so-new one is that the script was written by Nick Hornby, whose “High Fidelity” as both novel and movie is one of the touchstones of a generation. Adapting a memoir by Lynn Barber, Hornby gives this movie a braininess and subtle social accuracy it might not have had from another writer.

Not least of its attractions is how juicy the performance is by the great Alfred Molina as Jenny’s father, an actor so seldom allowed in movies to show all that he can do when allowed to start from scratch.

A small but solid triumph.

AN EDUCATION

Three and a half stars

STARRING: Carey Mulligan, Peter Sarsgaard, Alfred Molina

DIRECTOR: Lone Scherfig

RUNNING TIME: 100 minutes

RATING: PG-13 for mature thematic material involving sexual content, and smoking.

THE LOWDOWN: Middle-class British teen set on going to Oxford is diverted by the seductions of a mysterious older man.