Early in the film, director Ferrand, played by François Truffaut, says this in a voice-over of 'Day for Night'. A lot of the film illustrates that this is a very true sentence.
In his legendary Hitchcock book, Truffaut says at one point that it would be a nice idea to make a film about making a film, and Hitchcock agrees. Luckily Truffaut liked that idea enough to actually make this film, as 'Day for Night' is probably the best film ever made about making a film.
We are on the set of 'Meet Pamela'. 'Meet Pamela' is a love and revenge story, about a man falling in love with daughter-in-law. It looks very much like a pretty mediocre film. I doubt I would like it. But that's good, as it doesn't distract us from what's happening on the set, from the many characters.
We get to know the cast and crew of 'Meet Pamela': Julie Baker, a second generation Hollywood star whose nervous breakdown she's recovering from causes insurance problems; Alphonse, a very jealous, very neurotic French actor who's so madly in love with a girl he organizes the job of the script girl for her just to have her near; Alexandre, a veteran actor who played many lovers in his life, but is actually a closet homosexual; Severine, an Italian actress with an alcohol problem who used to play opposite Alexandre frequently in her career, but hasn't talked to him in years, maybe because she found out she had no chance to become his real-life lover. From the crew, we especially remember Joelle, the production assistant who almost seems to be more involved in the making of the film than director Ferrand (it is her who has the film's most often quoted line: "I'd drop a guy for a film, but I'd never drop a film for a guy"), Liliane, the girl who got the job as a script girl only because Alphonse wanted to have her around him, who doesn't really seem to be interested in the film - or in Alphonse; Odile, the makeup girl who also got a bit part in the film; Bernard, the prop man, who gives us with his every day work a look behind the scenes of a film; and the unit manager Lajoie, whose wife is always around and at one point shouts at the cast and crew because she just can't understand their 'immoral' behavior.
The film doesn't have a plot of it's own, but it shows us all these characters and their problems, trying to get a film made and getting over one catastrophe after the next, sometimes something as harmless as a kitten refusing to drink milk or Stacey, a supporting actress causing scheduling problems because of her pregnancy, sometimes something more serious as Alphonse refusing to go on acting after Liliane leaves the set with a stunt man, with even more complications to follow when Julie tries to cure Alphonse's neurosis. But not even a lethal car accident can stop the making of the film.
'Day for Night' also has brilliant performances, but three stand out: Nathalie Baye in her first notable performance as the omni-competent Joelle and Jean-Pierre Léaud, who never was better in his life than here as Alphonse, would make it a worthwhile film alone. But it is Valentina Cortese who steals the show as the fading actress Severine. Her scene opposite Alexandre in which she can't remember her dialog and suggests just saying numbers (she did the same when she worked with "Federico") is priceless.
At one point Ferrand says that a director is a man who is constantly asked many questions and sometimes knows the answer, and it is sort of a surprise that the one man who "invented" the auteur theory, which more or less says that a film is the director's work, makes a film that shows how many people's work is involved in the making of a film. But it is not only a film about people making films: Many of the characters (most notably Ferrand, Alphonse and Joelle) are film enthusiasts, and the entire film is a film from a film lover about film lovers for film lovers. It's Truffaut's best and shouldn't be missed by cinephiles.