It's December 1945, and the Second World War is finally over. Mathilde, a young French Red Cross doctor, finds herself in Warsaw treating the last of the French soldiers returning from the front. One night, a nun appears at the clinic, begging Mathilde to follow her back to the convent on urgent business. What Mathilde finds there is shocking: a holy sister about to give birth. As Mathilde enters the sisters' fiercely private world, secrets rise to the surface, and modernism and science clash with faith and tradition. The nuns go about their strict daily rituals, but inside the convent's chilly stone walls, echoing with their melancholic chants, a dangerous revolution is taking place. Based on true events, this thrilling drama will have you on the edge of your seat to see what happens. Superlative director Anne Fontaine, who brought us Adore (2013 Sundance Film Festival) and Coco Before Chanel, is at her best when transporting us to intimate worlds of women courageously crossing verboten boundaries.