Maigret is called to testify in court and reveals his doubts on the guilt of the accused

Maigret receives an anonymous phone call concerning the brutal murder of a woman and young child. The tip off concerns the woman’s nephew, a mild-mannered man by the name of Gaston Meurant. Maigret remains unconvinced of the man’s guilt and at his trial exposes some shocking truths about Meurant’s private life that may prove his innocence.