The former silent film star in the boarding house, desperate for a small role in a film, is played by Mary MacLaren, a former leading lady of the silent film era who, by the time this film was made, was working as a (sporadically successful) extra. Coincidentally, MacLaren's character is named Naomi; in the 1930's, one of MacLaren's silent era contemporaries, Naomi Childers, was also frequently employed as a background actress in Hollywood at MGM.
When the film was originally released, the names of Leslie Howard and Joan Blondell were above the title, and the name of Humphrey Bogart, who played a supporting role, was below. When it was re-released in 1948, Howard had been dead for 5 years, and Bogart was riding the crest of the wave, so the billing was re-arranged and Bogart was now top billed.
The character of Lester Plum bears some resemblance to Marie Osborne, a child actress in the silent era who returned to the film industry in the 1930's as an extra and stand-in. It's unclear if Osborne's life story was directly influential on this film or the role played by Joan Blondell.
Clarence Budington Kelland's story "Stand-In" was a 6-part serial in "The Saturday Evening Post" during February 13 - March 20, 1937.
This is one of two dozen Walter Wanger/Harry Sherman/Cinema Guild productions, originally released by United Artists, re-released theatrically in 1948 by Masterpiece Productions, and ultimately sold by them for television broadcast in 1950. It was first telecast in Chicago Monday 19 June 1950 on WENR (Channel 7), in Phoenix Sunday 30 July 1950 on KPHO (Channel 5), in Cincinnati Saturday 26 August 1950 on WKRC (Channel 11), in Los Angeles Sunday 3 September 1950 on KTLA (Channel 5), in Boston Sunday 17 September 1950 on WNAC (Channel 7), in Philadelphia Saturday 14 October 1950 on WFIL (Channel 6), in Detroit Sunday 22 October 1950 on WXYZ (Channel 7), in New York City Monday 18 December 1950 on WOR (Channel 9), in Pittsburgh Friday 26 January 1951 on WDTV (Channel 3), and in San Francisco Saturday 24 February 1951 on KGO (Channel 7).