The Man In The Hat sets off from Marseilles in a small Fiat 500. On the seat beside him is a framed photograph of an unknown woman. Behind him is a 2CV into which is squeezed Five Bald Men. Why are they chasing him? And how can he shake them off? As he travels North through France, he encounters razeteurs, women with stories to tell, bullfights, plenty of delicious food, a damp man, mechanics, nuns, a convention of Chrystallographers and much more, coming face to face with the vivid eccentricities of an old country.

Marc, in his 40s, is a professor of literature at the University of Lausanne. Still a bachelor — and still living with his sister Marianne in a huge, isolated chalet that they inherited when they were very young — he carries on one love affair after another with his students. Winter has almost ended when one of his most brilliant students, Barbara, suddenly disappears. Two days later, Marc meets Barbara’s mother, Anna, who wants to find out more about her vanished daughter.