A retired professor of American origin lives a solitary life in a luxurious palazzo in Rome. He is confronted by a vulgar Italian marchesa and her lover, her daughter and her daughter's boyfriend, and forced to rent to them an apartment on the upper floor of his palazzo. From this point on his quiet routine is turned into chaos by his tenants' machinations, and everybody's life takes an unexpected but inevitable turn.
As in bad plays, everyone always means exactly what he says and never has to think a second before saying it. There is no feeling for the complexity of the mental processes, for the mysterious ways in which the mind works.