Cut Song/Missing Trailer Scene: At least one other number was shot, then cut. In the original theatrical trailer, Jane Russell and Marilyn Monroe were shown among dancers, climbing the steps of a slide in a children's playground. The song was a French version of "Two Little Girls from Little Rock". Marilyn and Jane wear the costumes when Tommy Noonan corners them backstage in the French nightclub.
Non-Singing Voice: Marni Nixon supplied a few top notes for "Diamonds Are A Girl's Best Friend". She was supposed to dub all the singing, as the studio thought Marilyn's voice sounded silly — but she balked at that. She dubs the "no no no"s at the beginning and the line "these rocks don't lose their shape".
The ship model shown is the one used previously in Titanic (1953) and was refurbished to resemble the SS Ile de France, which is clearly named in the film. The model resides in the Marine Museum in Fall River, Massachusetts. Some of the ocean liner sets used were also left over from Titanic.
Reality Subtext: Lorelei is the Gold Digger of the pair. Marilyn's salary was considerably lower than Jane Russell's. In fact, despite being a top star in Hollywood, she was one of the lowest paid.
Throw It In!: At the end of the "Ain't There Anyone Here For Love" number, Jane Russell wasn't supposed to fall into the pool. That was an accident, but they left it it for fun.
Wag the Director: Marilyn Monroe kept insisting on retakes despite approval of takes by Howard Hawks. When Fox asked Hawks how production could be sped up he retorted: "three wonderful ideas: Replace Marilyn, rewrite the script and make it shorter, and get a new director."
"Diamonds Are A Girl's Best Friend" was going to feature Marilyn Monroe wearing a far more revealing dress, evoking Diamonds in the Buff. The studio thought it was too risque, and put her in the now-famous pink gown.
The studio wanted to re-team Monroe and Russell for the film How To Be Very, Very Popular, but both actresses passed on the project.