Both serve to tie a story together, to set a mood, to define a character. For instance, the opening scene in Maigret and the Spinster creates both a mood and framework for the book and is carried through to the end as a common thread. One impression above all remained with him, though he could not have explained why. The door, like the door of most cafes on this cold morning, was shut for the first time for months. Later on that same day Maigret downs a glass of rum at a bar, because of the memory of the smell of rum, croissants and coffee.
Smells also serve to define a place in Simenon's works.
Every little restaurant in Paris has its particular smell, and here, for example, against a background of aperitifs and spirits, a connoisseur would have distinguished the rather tart scent of the plain wines of the Loire. As for the kitchen, tarragon and chives were the predominant aromas. Wherever Maigret happens to be, the reader is introduced to the aroma defining that place whether it be the pungent smell of rotting fish in Fecamp or a description of Maigret's own brasserie, the Brasserie Dauphine with its wines of the Loire. In Maigret and the Burglar's Wife , the aroma of pernod is tied up with Maigret's memory of a case he had dealt with seventeen years before because he had been drinking pernod while he worked on the case. When he encounters the woman involved with the case again after so many years the entire memory becomes present and he again orders pernod.