Day for Night (1973) on Netflix

In Nice, the Studios La Victorine is producing the film "Je Vous Presente Pamela", about a French man that marries the English Pamela in England and brings his wife to France to introduce her to his parents. However, his father and Pamela fall in love with each other and she leaves her husband to live with him. The producer Bertrand and the director Ferrand invite British Julie Baker, who had a nervous breakdown and married her Dr. Nelson, to the role of Pamela. During shooting, the cast and crew are lodged in the Hotel Atlantic and Bertrand and Ferrand have to deal with problems with the stars Severine, an aging actress with drinking problems that affect her performance; the immature, spoiled and needy Alphonse; Julie that is emotionally unstable. But in the end, they succeed in completing the film.