In the wake of Greta Thunberg, the youth has been fighting for several months to save our planet. Leading the marches, on the front pages of the media as well as on social networks, young women have become, sometimes unintentionally, the key figures of this movement. Who are these women? Why are they so cheered and criticized at the same time? To better understanding of the commitment of Anuna and Adelaide (Belgium), Luisa (Germany), Lena (France), Leah (Uganda) and Artemisia (Brazil), we decided to follow them, but also to compare their struggle with that of another extraordinary woman who preceded them: Julia Butterfly. Twenty years ago, after spending 738 days on top of a majestic sequoia, this young American activist managed to save a thousand-year-old forest from being cut down. The film tells the story of the journey of these committed young women, each in their own way, but all driven by a unique energy, these "sisters in arms" tell their doubts and their desire.