The British author's satirical The Loved One was published in 1948, after Waugh had spent time in Hollywood observing the film industry and, of all things, the funeral industry. (The book is about a failed screenwriter who works for a cemetery and lives with a forgotten silent-film star.) Wilder and his co-writers reversed several elements, and there was no official connection between the movie and Waugh's book. But as commentator Steve Sailer points out, more than one contemporary source mentions it as an inspiration. Sunset Boulevard's cinematographer, John Seitz, said Wilder "had wanted to do The Loved One, but couldn't obtain the rights." And gossip columnist Hedda Hopper (who appears in the movie as herself) wrote that "Billy Wilder ... was crazy about Evelyn Waugh's book The Loved One, and the studio wanted to buy it."
An unintended comic touch not previously mentioned sounds like a scene from Waugh's novel (or the 1960s film made from it):
THE OPENING SCENE HAD TO BE SCRAPPED BECAUSE THE AUDIENCE FOUND IT TOO FUNNY.
Sunset Boulevard now begins with police cars racing to Norma Desmond's house, where a dead body is floating in the pool. But it originally began in the L.A. county morgue, with toe-tagged corpses—including Joe's—speaking to each other (in voiceover) about how they died. It was meant to be slightly humorous in a morbid way, but the audience at the first test screening found it flat-out hysterical, setting the wrong mood for the rest of the picture. When two more test audiences reacted the same way, Wilder cut the scene and the movie was saved.