Of the many things to note about the seven-minute lesbian sex scene in “Blue Is the Warmest Color,” a French drama about a teenage girl who becomes passionately involved with a slightly older woman, is how very long it seems to go on.

While there is little radical about lesbian sexuality on-screen these days (“The Killing of Sister George” led the way in 1968, and by 2010 “The Kids Are All Right” featured a lesbian couple who liked gay male pornography), the sex scene in “Blue” is certainly among the most graphic and physically intense.

It is brightly lit, so we see every crash of flesh against flesh, every pinch and grip. The younger Adele (played by Adèle Exarchopoulos) and Emma (Léa Seydoux) slap each other’s breasts, pull each other’s hair, scissor bodies, mount and dismount.

CNN wondered if it might be the “sexiest film ever.” The IFC Center in Greenwich Village, which is showing the film, has been criticized by a parents group for allowing teenagers into the NC-17 film. (The Flicks art house cinema in Boise, Idaho, has declined to show the film.)