Everyone has a secret. Twins Sarah and Gaëlle near 25; for ten years, Sarah has been a fundamentalist Carmelite in a Brazilian convent, and Gaëlle has been in prison for a heinous crime. Sarah comes to the attention of Fr. Joachim, a priest and physician; he can find no cause for her debilitating abdominal pain. When Sarah and he are transferred to Paris, Joachim looks for Gaëlle, now on probation and finding no respite from society's approbation. An enterprising reporter is digging into Gaëlle's life, the mother superior of Sarah's convent hovers over her, and Joachim investigates the phenomenon of twin's symmetry. Is there any release from the past?