(Hat tip. Simon B.)
A technique I have for judging if a film is really any good is to imagine it remade with the Carry On team and decide if that version would be an improvement.
Thus, "Carrry On Godfather" probably wouldn't be better than the original, but "Carry On Betty Blue" could be a work of genius.
Betty (Hattie Jacques) and Zorg (Sid James) are passionate lovers who live in a shack on the beach. Zorg narrates the story of their relationship via voiceover. He describes Betty as “like a flower with translucent antennae and a mauve plastic heart”. She yearns for a better life and quit her last job as a waitress. Zorg's boss asks him to paint the 500 shacks that populate the beach—a fact that he keeps from Betty who thinks they only have to do one. She takes on the project with enthusiasm that quickly turns to anger once she learns the actual number. In response, Betty covers the boss’s car with pink paint .... and then the fun really begins ...