Detective Jules Maigret is two years into retirement when Bernadette Amorelle, a widow with influential family ties, turns up at his door. Her granddaughter has been found dead in the Seine, and she's insistent that Maigret take the case. When Maigret arrives to investigate, he discovers that the girl's father, Ernest Malik, is an old acquaintance from his days at lycée—a man Maigret instinctively disliked, even all those years ago. When Malik's younger son also goes missing, Maigret delves into the mystery and uncovers old, deadly secrets that will destroy more lives before they are finally revealed.