Virtually all of the interactions between Totò and Aldo Fabrizi were improvised. More often than not, the directors would simply feed them the first line and let them be in charge of the scene.
Movie director Steno stated in an interview that when the plot was shown to Totò for the first time, he said: "It's wonderful, but what should it have to do with me? This is a movie for Fabrizi".
By contract, Totò didn't work in the morning, because he believed that "one cannot make laugh in the morning". This led to problems while filming exterior scenes, in particular the chase scene required 15 days. At the end Totò accepted to film in the morning.
Director Mario Monicelli stated that Totò and Aldo Fabrizi got along particularly well during filming and acted very collaboratively with the rest of the cast and the direction crew. The experiment of making work two great actors together initially bothered the production despite Totò and Fabrizi being close friends in real life, but it then went so well that during filming other two movies were planned for the duo for being produced shortly after. However, those movies were then made with other actors: they were Bertoldo, Bertoldino e Cacasenno (1954) and Cani e gatti (1952). Totò and Fabrizi worked then together again in the successful comedies I tartassati (1959) and Totò, Fabrizi e i giovani d'oggi (1960).
The son of Aldo Fabrizi stated in an interview that the filming of the scene at the inn was very difficult because his father and Totò couldn't stop laughing.