Bernardo, the youth thing is getting a little old ...

The older Bernardo Bertolucci gets, the more you have to share his heedless love of youth for youth’s sake to be enthusiastic about his films. If you don’t glow with the same pleasure he feels when the characters in “The Dreamers” alternate brashness with callow immaturity, you’re going to be in for a very long evening.

This despite the fact that the Italian director is as enamored of youthful bodies as he is of souls, as entranced with the supple physiques of his Paris 1968 protagonists as he was with Liv Tyler in “Stealing Beauty,” and he shows enough of them to get “The Dreamers” a rare NC-17 rating. That rating, which takes into account close-ups of male and female genitalia as well as a variety of simulated sex acts, is the best thing about “The Dreamers.” It’s gratifying to have unapologetically adult material of whatever quality available from a major studio, and both Fox Searchlight and parent company 20th Century Fox deserve a vote of thanks for defying Hollywood’s hidebound reluctance to release NC-17 films.

In truth, how you feel about “The Dreamers” depends on more than your tolerance for young people; it also depends on your willingness to indulge a director who’s been so routinely deified as the taboo-breaker of “Last Tango in Paris,” whose “The Last Emperor” won nine Academy Awards, that no one seems to have noticed the increasing indifference of the thematic side of his work.

That’s partly because from the point of view of technique, Bertolucci, most noticeably in his masterful “The Conformist” and the early parts of “1900,” is a great cinematic sensualist, someone whose images, elegant camera movement (Fabio Cianchetti is the cinematographer here) and use of color invariably please the eye.

What he’s given us here is an older man’s dream/memory/fantasy of being young and in Paris in a year when youth seemed ready to rule the world. Based on a script by Gilbert Adair taken from his own novel, “The Dreamers” is about a trio of young people who play increasing bizarre psychosexual mind games as they hole up in an apartment as Paris prepares to explode on the streets below them.

There’s nothing intrinsically objectionable about this; the problem is that Bertolucci’s obsessions turn out to have the tedium of impenetrable insularity: There’s no way into them for anyone but him. Once you get past admiring bodies of both sexes, the characters are so feckless and jejune they present little that’s capable of engaging let alone holding our interest.

After a credits sequence that artfully pans down the Eiffel Tower, “The Dreamers” shows us the nearby Palais de Chaillot, then the home of the Cinematheque Francaise, as narrator Matthew (Michael Pitt) announces that “only the French would have a cinema inside a palace.”

An unconvincingly shy and awkward naif from San Diego, of all places, Matthew is the classic 20-year-old American abroad, spending a year in 1968 Paris learning French. Despite looking like a cross between James Dean and Chet Baker, young Matthew hasn’t made any friends and spends almost all his evenings at the cinematheque, watching films like Sam Fuller’s “Shock Corridor” and anything at all by Nicholas Ray.

When Matthew stumbles on a demonstration to protest the ouster of cinematheque founder Henri Langlois, he meets brother and sister Theo (Louis Garrel) and Isabelle (Eva Green). They are a headstrong, volatile pair, almost a parody of French youth with their incessant cigarette smoking and insouciant attitudes, and after the trio spend the evening trading bon mots about Ray and Godard, Matthew is so entranced he actually says, “I didn’t want that night ever to end.”

Actually, the cinephile nature of its three protagonists is “The Dreamers’ ” most charming and possibly most sincere aspect. Adair’s paean to what he calls the freemasonry of film buffs, the people who sit in the first rows “because they want to receive the images first, while they’re still new,” is nicely done. So is Bertolucci’s lovely habit of intercutting clips from the pictures these three discuss as if they were more important than life itself, classics like “Queen Christina,” “Scarface” and Tod Browning’s “Freaks,” into his own film.

After a dinner at his new friends’ home at which the entire family is inexplicably charmed by Matthew’s airheaded philosophizing, the parents conveniently leave for a month’s vacation and Theo and Isabelle invite Matthew to abandon his dreary hotel and move in with them. Attracted and a bit perplexed by their easy sensuality, he readily agrees, writing his mother, “I’m getting in with the right kind of people.” Not quite.

That month in the apartment is initially set up as a familiar clash between American innocence and European experience, as Matthew doesn’t quite know how to react (not that anyone would) when Isabelle says things like: “You have the most beautiful pair of lips. They’re so red and ripe and luscious. Can I touch them?”

Things don’t get much better when the siblings, who claim to be twins, draw Matthew into complex Sadean manipulations that feel more like sexual imbroglios of the ‘80s and ‘90s than the ‘60s. When Matthew says “You’re a strange one, Theo,” few will be tempted to argue.

Matthew is too callow and the putative twins are too shallow (or is it the other way around?) to make any of this interesting. When interludes out of bad surrealist plays like eating garbage for dinner are thrown in, “The Dreamers” makes decadence look no more than tiresome. As Spanish director Pedro Almodovar might put it, if this is liberation, tie me up and tie me down.

With a soundtrack that includes Jimi Hendrix and Janis Joplin as well as French stalwarts Edith Piaf and Charles Trenet, “The Dreamers” does have its pleasures, but the feeling is inescapable that the person most pleased is Bertolucci himself. In essence he is the dreamer of the title, as eager to retreat into this hermetic world of his own creation as his characters are into theirs. Fair enough, but why does he have to drag us along with him?

*

‘The Dreamers’

MPAA rating: NC-17, for explicit sexual content

Times guidelines: Full frontal nudity for both sexes and graphically simulated sexual acts

Michael Pitt...Matthew

Louis Garrel...Theo

Eva Green...Isabelle

Robin Renucci...Father

Anna Chancellor...Mother

A Recorded Picture Co., Peninsula, Fiction co-production of a Jeremy Thomas production, released by Fox Searchlight Pictures. Director Bernardo Bertolucci. Producer Jeremy Thomas. Screenplay Gilbert Adair, based on his novel. Cinematographer Fabio Cianchetti. Editor Jacopo Quadri. Costumes Louise Stjernsward. Production design Jean Rabasse. Running time: 1 hour, 55 minutes.

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