Maigret investigates the circumstances surrounding the attempted suicide of a countess and the death of a multi millionaire, both seemingly strangers but staying in the same hotel.

When multi-millionaire David Ward is found dead in the same hotel as a countess who attempted suicide only hours earlier, Maigret presumes that the two cases are connected. When the countess flees Paris after the murder Maigret follows her to Nice and then to Switzerland to uncover the truth.