On the DVD, Taina Elg says the original cast was supposed to include Cyd Charisse as the American girl, Leslie Caron as the French girl and Kay Kendall as the English girl. Cyd Charisse decided to do Silk Stockings (1957) instead, so Mitzi Gaynor took her part. At one point, Kay Kendall didn't want to do the film and Taina Elg was tested for her part. Ms. Kendall took the part after all, but then Leslie Caron withdrew. Tania Elg was tested for THAT part and received her first major film role.
Heard in the background between the stage performances is a snippet of "Be a Clown." Cole Porter wrote this for, "The Pirate," and he wrote the rest of "Les Girls" songs. People might think that they hear a snippet of, "Make 'em Laugh," from "Singing in the Rain." But that song was based on/stolen by Arthur Freed from Cole Porter. (But that's another story.)