Ladies Of The Chorus (1949) [colourised]

Marilyn Monroe stars in this romantic comedy, the first major role of her career.

Plot (from Wikipedia):
Peggy Martin (Marilyn Monroe) and her mother Mae (Adele Jergens) both work as burlesque chorus girls. After star Bubbles LaRue quits, the stage manager Joe asks Mae to do a specialty number, but Mae secretly arranges for Peggy to do the number instead, and her performance is so good that she is given the starring spot.