France, 1918. In the final days of the First World War, a young Chinese woman, Pauline Deng, runs away from her uncle's home in Paris to evade a marriage being arranged for her in Shanghai. To prevent the union, she needs the help of her cousin Theo, who is working as a translator for the Chinese Labour Corps in the French countryside. In the town of Noyelles-sur-Mer, Camille Roussel is planning her escape from an abusive marriage, and to end a love affair that can no longer continue. When Camille offers Pauline a room for her stay, the two women become friends. But it's not long before Pauline uncovers a perilous secret that Camille has been hiding from her. As their dangerous situation escalates, the two women are forced to make a terrible decision that will bind them together for the rest of their lives.