Leslie Caron had suffered from malnutrition during World War II and was not used to the rigorous schedule of filming a movie. Because she would tire so easily, she was only able to work every other day to the annoyance of Gene Kelly.
Oscar Levant, more of a pianist than an actor, signed onto the film because he was a friend of George Gershwin. According to Levant, the cast and crew disliked Gene Kelly due to his condescending attitude and snide remarks.
Even though Vincente Minnelli is credited as the sole director, he was sometimes tied up with his divorce from Judy Garland and other directing projects, leaving Gene Kelly to take over the directing duties much to the dismay of the cast and crew.
Gene Kelly discovered Leslie Caron while vacationing in Paris where he saw her perform in the Roland Petit company "Ballet des Champs Elysées". However, as with his relations with Debbie Reynolds and Cyd Charisse, the relations between Kelly and Caron soured due to his relentless criticism and cruel insults on the set. Citing Kelly's rude behavior towards the cast and crew over multiple films, MGM released him from his contract in 1957.
Oscar Levant's dream sequence is a tribute to Buster Keaton. In the opening sequence of The Play House (1921), Keaton played every role: the conductor, a stage hand, every member of the orchestra, all nine actors on stage, and each member of the audience.