After Agnès Varda filmed her friend Jane Birkin in 1988, in the film Jane B. par Agnes V., now Birkin's daughter, the extraordinary actress Charlotte Gainsbourg, daughter of Serge Gainsbourg, makes her directorial debut with Jane par Charlotte, an intimate and touching portrait of her mother. The two use the camera to open up to each other and, through a film, rediscover the bond that unites them, after the separation that followed the death of Kate Barry, Charlotte's sister and Jane's daughter.