Isabel Walker (Kate Hudson) travels to Paris to visit her sister Roxy (Naomi Watts), a poet who lives with her husband, Frenchman Charles-Henri de Persand (Melvil Poupaud), and their young daughter, Gennie. Roxy is pregnant, but her husband has just walked out on her without explanation. Isabel discovers that he has a mistress, a Russian woman named Magda Tellman, whom he intends to marry after securing a divorce from Roxy. Roxy refuses to divorce him.