Gentle Monster, the latest work of Austrian auteur Marie Kreutzer, had its world premiere at the Cannes Film Festival late on Friday night. The dark and disturbing drama, which is playing in competition at the fest, was enthusiastically cheered by the audience inside the Grand Théâtre Lumière, especially when its leading lady, Léa Seydoux, was shown on the screen. Indeed, the film’s standing ovation clocked in at six minutes, but only came to an end because Kreutzer accepted a microphone and began addressing attendees; I suspect that, if not interrupted, it would have gone on for quite a bit longer. The subject matter of the film is heavy, to be sure: a woman (Seydoux) who is happily married and the mother of a young child has her life upended when — spoiler alert — the authorities arrest her husband (Laurence Rupp) for possession and distribution of child pornography. It’s not immediately clear if her husband was involved in the material’s production and/or if their own child was among those exploited, but the woman knows that her …