Maigret and the old people

Maigret is called to the home of Armand de Saint-Hilaire, a highly respected official who has been found shot dead in his study by his housekeeper. After interviewing everyone concerned Maigret is at a loss to the identity of the perpetrator until he comes across a series of letters from the past fifty years between the victim and a recently widowed woman. As Maigret uncovers the details behind the two's relationship he gets closer to discovering the tragic truth behind the official's demise.