As soon as Blue Is the Warmest Color premiered in Cannes last May, frenzied discussion engulfed the film. Whether people found it exhilarating or exploitative, it seemed no one could shut up about this three-hour French saga about first love between two young women. The seven-minute sex scene monopolized much of the conversation, with a video montage that captures the responses of real lesbians eventually going viral. After the jury awarded the Palme d'Or to the film's director as well as to its two stars, attention turned to the excruciating treatment the actresses said they had received on set—one said she felt like a prostitute. The director, Tunisian-born Abdellatif Kechiche, claimed he wanted the film's release canceled.

How fortunate we are that Kechiche didn't get his way (he ultimately recanted too). Because for all the hooting—laudatory or incensed—it has unleashed, Blue Is the Warmest Color isn't strident or demagogic. Instead, the film spends its 179 minutes slowly wringing you out like an old rag, until you're finally tossed roughly over the line, depleted, devastated and stunned at what has just transpired.

What transpires is at times volatile but, just as in real life, more often mundane. The film charts the evolution of the relationship between the working-class Adèle (Adèle Exarchopoulos), who is in high school when the film begins, and the art student Emma (Léa Seydoux), who is a few years older. From the initial moment the two lock eyes—after a heavy-handed discussion in Adèle's French class about love at first sight—their connection is as electric as the shock of blue through Emma's hair. Sometimes that connection plays out explosively, as in the aforementioned sex scene, which astounds more for its arguably excessive length than for its explicit images. But there are far more scenes devoted to quotidian routines and banal conversation. Minutes after exiting the theater, you're unlikely to recall much of what Adèle and Emma talked about. But you'll remember the frantically searching expressions on Exarchopoulos' face, the looks of cool composure on Seydoux's, the unrelenting urgency and desperation that infuse their exchanges. Anyone who's known the thrill of love and the psychological wringer of its dissolution will recognize the emotions depicted onscreen. Desire, we're reminded, can torture just as much as it can liberate.

Kechiche allows the characters to develop gradually, and we see Emma building a modest career as a painter and Adèle finding work as a primary-school teacher. The two share gorgeous moments of connection, catching each other's gaze across the table while eating dinner with Emma's family, as well as devastating instances of betrayal and destruction. In one scene, Adèle has been tossed out of the apartment they share, and Exarchopoulos staggers down the empty nighttime streets, keening and convulsing. The camera remains tight on her face as her tears and mucus and saliva run together, her emotions physicalized in these fluids.

Much of the film is spent on close-ups of Exarchopoulos: fingers tugging on her messy ponytail, wisps of hair caught in her eyelashes, eyes darting, lips hanging open, mouth filled with spaghetti Bolognese. It's an aesthetic approach that could have made the character of Adèle one of feral simplicity, but Exarchopoulos' naturalistic performance, devoid of histrionics, will knock the wind out of you. (That the actress was 18 at the time of shooting only boggles the mind further.) Seydoux's Emma is self-possessed and charming, but this is ultimately Adèle's movie, and Exarchopoulos' performance is one of the year's best.

As much as response to Blue Is the Warmest Color has focused on the depictions of lesbian sex, the characters' sexual orientation isn't the crux of the film. It's more than incidental—we see Adèle harassed by classmates who call her a "dirty dyke"—but this isn't a gay-rights drama. It's an epic tale of love between two people who just happen to be women, and that's hopefully what will allow it to endure. 

Critic's Grade: A-

Blue Is the Warmest Color is rated NC-17. It opens Friday at Cinema 21.