“Shall We Kiss?” is a sensational date movie. Writer-director-star Emmanuel Mouret restores the first kiss to its romantic primacy. He undresses his characters – physically and psychologically – with a light comic touch. They’re amorous idealists. They must be sure that they’re in love before they bank their future on their passions. They must commit to each other totally before they hurt anyone else in their lives.

In the framing story, a smart, soulful blonde, Emilie (Julie Gayet), a Parisian fabric designer on her first trip to Nantes, meets a stranger, Gabriel (Michael Cohen), who ends up driving her to her hotel. They hit it off so well that it seems natural for Gabriel to offer a kiss: a buss to remember him by. Emilie says there’s no such thing as a kiss without consequence – and proceeds to tell a story to illustrate her point.

Mouret cleverly sets up the film-within-a-film as the most innocent farce imaginable about adultery. It’s about a man and a woman who experience the equivalent of love at first sight though they’ve long been bosom buddies. Nicolas (played by Mouret), is a math teacher with a shambling, earnest charm. Judith (Virginie Ledoyen) is a lab worker who sparkles with cheer and is married to the equally good-natured Claudio (Stefano Accorsi).

The complications start when Nicolas, with hilarious politeness, requests physical affection from Judith as therapy a few months after his last girlfriend has left the country. He and Judith kid themselves into thinking it’s a favor between pals – a haute-bourgeois version of friendship with benefits. But she finds herself strangely stirred. And Nicolas can’t stop thinking about her even after he finds a fetching new girlfriend, Caline (Frederique Bel).

What makes the first hour of the movie feathery and funny is they way these two characters both experience and analyze their pleasures, almost simultaneously, whether they’re petting like school kids or stealing time in a bedroom during a party. They can’t believe what they’re doing, yet they can’t deny their need for it. Mouret’s matter-of-factness as a director derives from his confidence in himself as a droll, improbably ardent performer and in his co-stars’ ability to merge sexiness, playfulness and gravity. There’s nothing smarmy about Nicolas and Judith’s shenanigans. When the movie swerves into pathos two-thirds of the way through, these newly sexualized innocents seem out of place in a tragicomedy. And the action loses its bracing directness in an improbable and elaborate subplot involving Caline and Claudio. Yet the resolution (or irresolution) of the framing story compensates for these needless complications.