Actor Allusion: In the musical— Glenn Close portrays a lonely troubled woman slowly driven to insanity due to her unhealthy obsession with a man. Eventually she's pushed over the edge and goes on a murderous rampage... But enough about Alex Forrest in Fatal Attraction.
Beam Me Up, Scotty!: People often misquote this movie's famous line as "I'm ready for my closeup, Mr. DeMille" when it's actually, "Alright, Mr. DeMille, I'm ready for my close-up".
Career Resurrection: Averted. Gloria Swanson's film career was not revitalized by the film. She was disappointed to see that all the parts she was offered subsequently were watered down versions of Norma Desmond. Ultimately she retired completely from films, making only sporadic appearances, notably in Airport 1975.
Executive Meddling: Probably for the better. The original cut of the film involved Joe Gillis's corpse talking to other corpses in the morgue, which made test audiences laugh uproariously. All that survives of this early opening consists of script pages and some silent footage of morticians transporting and storing the corpse.
Irony as She Is Cast: Despite the fact that Erich von Stroheim plays a butler/chauffeur, he could not drive in real life. During the scenes in which he drove, the car was towed by another car. In the scene in which he drives Norma Desmond to Paramount Pictures at the studio gates the car was pulled by men with an out of camera rope.
Meta Casting: Norma Desmond, a forgotten silent film star, was played by Gloria Swanson, a forgotten silent film star. Her butler, Max von Mayerling who used to be a leading silent film director is played by Erich von Stroheim, who used to be a leading silent film director. (Needless to say, Swanson took her fall from stardom with much more grace and sanity than Norma.)
Also, Cecil B. De Mille plays himself, Hedda Hopper (a gossip columnist) plays herself, and the "Waxworks" (Norma's friends who are other forgotten silent film stars) are all played by...other forgotten silent film stars. (And Buster Keaton). In general, this film is regarded to be one of the biggest cases of Meta Casting in Hollywood.
Method Acting: According to Gloria Swanson's daughter, Michelle Amon, her mother stayed in character throughout the entire shoot, even speaking like Norma Desmond when she arrived home in the evening after filming. On the last day of shooting, Swanson drove back to the house she, her mother and daughter shared during production, announcing "there were only three of us in it now, meaning that Norma Desmond had taken her leave."
Money, Dear Boy: Cecil B. DeMille agreed to do his cameo for a $10,000 fee and a brand-new Cadillac. When Billy Wilder went back to him later to secure a close-up, DeMille charged him another $10,000.
Mean Character, Nice Actor: Gloria Swanson was worlds more stable and down-to-earth than Norma Desmond. Very notably, Swanson handled her change of fortune much better than Desmond: When it became apparent that her film career was over (at least in any roles besides a White-Dwarf Starlet) she focused more on her theatre and television prospects, which, while nothing earth-shattering, were fairly successful and kept her in the public eye.
Reality Subtext: Norma is played by Gloria Swanson, who was a silent film star, and worked with Cecil B. DeMille. Max is played by Erich von Stroheim, who was a silent film director.
The movie that Norma and Joe watch together was comprised of footage from Troubled ProductionQueen Kelly (1929) - directed by none other than Erich von Stroheim.
And Cecil B DeMille referred to Swanson as "young fella" when both were getting started in Hollywood.
The Waxworks, of course, were real former Hollywood stars then considered has-beens, including Buster Keaton.
Starring a Star as a Star: Silent film era star Gloria Swanson plays all-but-forgotten silent film ere star Norma Desmond (and silent film actor and director Erich von Stroheim plays Desmond's butler Max, also her former silent film director).
Those Two Actors: After the success of the film, this was attempted with William Holden and Nancy Olson; they appeared in three further films together, but none of them was really successful.
Typecasting: Filmmakers just rehashed Norma whenever they wanted to give Gloria a part in a film after that, and some people still confused Swanson with Desmond.
Several other old-time actresses were considered for the role of Norma Desmond, including Greta Garbo, Pola Negri, Mary Pickford, and even Mae West, who was turned down after one meeting with the producers, who said they realized that she was still both too dignified and too pretty to believably sell a has-been character like Norma.
Stephen Sondheim began work on a musical version, before the release of Andrew Lloyd Webber's play. He abandoned the project due to Billy Wilder saying that he'd prefer a Sunset Boulevard opera to a musical.
Working Title: The writers feared that Hollywood would react unfavorably to such a damning portrait of the film industry, and so the film was code named A Can of Beans while in production.