After being shot when chasing a disturbed man who has mysteriously jumped off a moving train, Inspector Maigret is taken to the small town of Bergerac to recover. There he discovers that a deranged killer who pierces his victims hearts with a needle is terrorizing its citizens. Maigret begins to conduct the investigation from his sick bed at the Hotel dAngleterre, ably assisted by Madame Maigret and his old friend Leduc. But when he interrogates the local dignitaries, including the doctor and the prosecutor, he comes up against a wall of resentment and silence.