The press materials for The Girl Next Door, which opened in April, tell us that when its 18-year-old hero falls for the girl of the title only to discover that she is an ex-porn star, "his sheltered existence begins to spin out of control. Ultimately, Danielle helps Matthew emerge from his shell and discover that sometimes you have to risk everything for the person you love — as he helps her rediscover her innocence." Some trick! It was accomplished, by the way, by having Danielle help Matthew make a porn video. It reminds me of a report titled "It’s Never too Late to be a Virgin" that ran a couple of years ago in the New York Times. The idea was that religious women who had strayed, or who had got religion since a promiscuous phase, would by abstaining from sex for a time expect to reclaim something called "secondary virginity"and so recapture the thrill of being a virgin on their wedding night.

Getting carried away with her theme, the Times reporter went on to declare that the phenomenon is "increasingly the norm for many brides-to-be across the South," on account of the clash between "the modern reality of premarital sex and the traditional disapproval of it in the Bible Belt." Of course, you have to take anything that the New York Times says about the South cum grano salis, but even if there are some secondary virgins out there, most of those caught up in "the modern reality of premarital sex" must be supposed to respond to the loss of innocence by insisting that it’s no loss at all — or that, in fact, it’s a gain. Who wants to be a sexless spinster of a certain age who has never experienced what the New York Times is pleased to call "modern reality"?

My generally indulgent editors have decreed that they cannot afford me the space that, I fear, would be necessary to refute this heresy, so I must confine myself here to pointing out one of the other things we lose when we lose our innocence is romance. For romance, though it is all about sex — that’s of course — still depends on the idea and, I would say, the reality of chastity. Grant me this and you’ll see what a problem for romance it is that the culture of promiscuity is now so taken for granted that any recurrence to the idea of good girls and bad girls seems merely a ludicrous anachronism. In Kevin Smith’s new movie, Jersey Girl, the ingenue, played by Liv Tyler, is working on a paper on masculine consumption of pornography for her women’s studies course when she meets her young man, a tragic widower and single-father played by Ben Affleck, as he attempts to rent a pornographic video without his seven year old daughter’s noticing.

I found it interesting that the seven-year-old’s innocence is still something that Mr Smith (presumably) thinks is worth protecting, even though it apparently is a commodity of no value in someone as old as Miss Tyler. On learning that Mr Affleck’s character has been celibate for the seven years since his wife (Jennifer Lopez) died in childbirth, she responds by telling him that "You gotta get back up on the horse, man!" and offers him what she charmingly calls a "mercy jump" to that end.

For some reason, the film is reticent about how many other lucky guys have been the beneficiaries of a similar service from Miss Tyler’s character, but it’s pretty clear that the number of hitherto horseless riders is not zero. Or maybe she only knows the terminology of mercy jumping from the pornography she watches in pursuit of her studies? Either way, it’s obvious that Mr Smith sees no reason why someone so sexually experienced should not be the ostensible heroine of his little romance. Curiously, however, it turns out to be sadly unromantic, or more of a romance between the father and the daughter, as Ben decides not to go for a high-stress, high-paying job so as to spend more time with her. The jumping women’s studies scholar may be expecting to hang around for a while, but if so it is clearly on the understanding that she’s not Ben’s first love, even among living females.

Innocence will out, I guess you could say. And romance demands it. I made a similar point in these pages a year or so ago in reviewing the film of Chicago: namely that a musical so cynical could never be anything but a kind of monstrosity — a joke at the expense of conventional pieties (and conventional musicals) but without anything of its own to offer beyond a corrupt and sardonic fantasy of female empowerment. Even here, it seems, the women’s studies movement is popping up in order to vitiate romance! So it does too, perhaps, in D.J. Caruso’s Taking Lives in which the odd-couple romance between the smartest FBI agent in Washington (Angelina Jolie) and a serial killer is reduced to a narrow escape from an unlucky pick-up and a one-night-stand. Just imagine! she was in bed with that guy! Oooh! She didn’t know that the guy she fancied happened to be a serial killer. She thought he was a nice artist. It might have been better if she had picked him just because he killed people, but then she would have been an "enabler" of an "abuser" and so disqualified from appearing a feminist hero.

Anyway, it’s better when it’s the woman who unites the attractions of sex and death, like Keats’s "Lamia" or "La Belle Dame Sans Merci." The classic romance paradigm comes when the hero is torn between a good girl and a bad girl as in Wagner’s Tannhäuser — in my recording of which, conducted by Otto Gerdes, the good girl, Elizabeth, is sung by the same woman, the wonderful Birgit Nilsson, who sings the bad girl, Venus. Obviously, this is a lot harder to do when there’s no longer any such thing as a bad girl.That’s what makes it all the more remarkable that Jean-Paul Rappeneau, the French director of Cyrano de Bergerac (1990) and Le Hussard sur le Toit (1995) — the latter oddly titled for the American market The Horseman on the Roof — has recreated this classic form of romance in our Movie of the Month, Bon Voyage. A poor young writer, Frédéric Auger (Grégori DerangPre), is devoted to an actress, Viviane Denvers (Isabelle Adjani), who is the toast of pre-War Paris. She uses his devotion, and his sense of chivalry, to avoid prosecution for a murder. Frédéric willingly goes to jail for her without a peep.

Before he can be prosecuted, however, the Germans invade France, and he escapes from prison, making his way along with the Parisian élites — including Viviane and her cabinet minister lover (Gérard Depardieu) — to overcrowded and scheming Bordeaux. Along the way he meets the elderly Professor Kopolski (Jean-Marc Stehlé) and his young assistant, Camille (Virginie Ledoyen), who are trying to get the world’s supply of heavy water, important for nuclear bomb-making, out of the country before it can fall into the hands of the Germans.

It never occurs to us to ask if the incomparable Virginie is a virgin. Even to raise the question would be an impertinence. She is the only actress I know of in any language today who can persuasively play that classic Kathryn Hepburn part of the girl who is mousy and plain until she takes off her glasses, smiles and lets down her hair, when she suddenly appears dazzlingly beautiful. This of course makes her ideal as the ideal to which Frédéric’s better and patriotic self must aspire. To save France and the world from Naziism is the least he can do to win the love of such a woman, and the least that her pure love can demand of him. Somehow the idea of a "mercy jump," in spite of Frédéric’s six months in prison, never comes up.

Rappeneau’s film is easy to appreciate on many levels. The characters are attractive, the plot is ingeniously contrived and constantly suspenseful and the sense of history, while perhaps not accurate in every detail, is close enough to what we know of the period to lend the picture a sense of momentousness. But above all, it is like a breath of fresh air amid the sulphurous smokes of sexual desire to find that it is possible to believe, if only for a couple of hours, that the spirit of chivalry and romance might once again be awakened to life by a virtuous maiden.