A Paris college professor, Julien sees his family happiness crumble when police officers come to their home to arrest his wife Lisa for the murder of her boss. The young woman is taken away in handcuffs, in front of her incredulous husband and their two-year-old son, Oscar, who cries as the events unfold. Faced with overwhelming evidence of her guilt, Lisa is sentenced to 20 years in prison.
When all appeals have been exhausted, Julien, convinced of his wife's innocence, plans her escape from prison. With help from an ex-con, the teacher, who has never had anything to do with shady dealings, patiently hatches a plan, while continuing to take care of Oscar.