In the 1800s, a stormy love relationship develops quickly between a young medical student and a woman believing herself to be the daughter of his scientist uncle, the student having never heard of her before their chance encounter and both unaware that she is the result of the scientist's illegal experiments with artificial insemination..

Sixteen-year-old Diane exists exclusively through her mother's gaze. But this intensely close bond between Diane and her mother, Sophie, is becoming increasingly problematic for the teenager. At high school, she would like to be loved like she is at home and expresses it in an awkward way like when she exchanges a favor for a look, in the toilets. A loudmouth, provocative, and seeking attention, Diane tries to stand apart from her mother and wishes, during a weekend, to live like an adult.