Paris 1933. Two days before Christmas the express train to Strasbourg crashes into a local train in the darkness outside Paris. On board is Gilles Malroux a man with a reason to avoid the police. He is badly injured in the crash but to avoid capture he swaps identity papers with one of the other victims. Gilles tries to flee in the dark but finds himself taken to the house of a woman he doesn't know. She nurses him. But is the bitter medicine in the spoon she puts to his lips healing him or harming him? Meanwhile Camille Malroux is informed that her brother is seriously injured in hospital. But although the injured man has his papers he is not Gilles. Only by digging to discover the true identity of the bandaged man in the hospital bed can she hope to trace Gilles.
