Cécile had come to the Parisian police headquarters to tell her secret to Inspector Maigret. But Maigret, in the course of a busy day, lost track of Cécile – until she disappeared. And when Maigret, now worried about her, want to her apartment to see what he could find – well, by then it was too late, for Cécile was dead. Now Maigret must uncover her secret.