Judy Holliday's last film.

Judy Holliday won Broadway's 1957 Tony Award as Best Actress (Musical) for "Bells Are Ringing," a role she recreates in this film version.

Except for two uncredited parts in her first two films, this was the only color film Judy Holliday made.

This was both Arthur Freed's and Vincente Minnelli's last musical for MGM.

Frank Gorshin (Blake Barton) is doing an impression of Marlon Brando. Gorshin was one of Hollywood's greatest impressionists, along with Rich Little. He would become famous for playing "The Riddler" on Batman (1966), appearing in ten episodes, and a role for which he was nominated for an Emmy.

"Is It a Crime?" (music by Jule Styne, lyrics by Betty Comden and Adolph Green), sung and recited as a comic inspirational message by Judy Holliday to Dort Clark, was deleted from this movie. The routine as shot still exists and can be watched on the DVD issued by Warner Home Video. Since Miss Holliday sing-speaks much of the song live, the orchestration would have been filled in later, and she performs only with what seems to be a violin.

Hal Linden's movie debut. He was the understudy for Sydney Chaplin, who starred as Jeffery Moss on Broadway. Linden eventually performed the role with Judy Holliday.

A song written for the picture, "My Guiding Star" (music by Jule Styne, lyrics by Betty Comden and Adolph Green), sung by Dean Martin, was deleted. The vocal as filmed still exists and is featured on the DVD from Warner Home Video.

Sydney Chaplin won the 1957 Tony Award (New York City) for Supporting or Featured Actor in a Musical for his performance as Jeff Moss in "Bells are Ringing".

In the middle of the song "Just In Time", Judy Holliday slips in an impersonation of Señor Wences' "S'alright" catchphrase.

Ella sings about going back to the Bonjour Tristesse Brassiere Company. The novel "Bonjour Tristesse" (French: "Hello Sadness") by Françoise Sagan was published in 1954, and was translated into English in 1955. It was considered quite racy, sort of a "Fifty Shades Of Gray" for the time. Because of this, the phrase took on a salacious connotation in the U.S.

Judy Holliday recreated her Broadway role as Ella Peterson. Others who recreated their Broadway roles in the movie were Jean Stapleton as Sue, Dort Clark as Inspector Barnes, Bernard West as Dr. Joe Kitchell and Doria Avila as Carl. The original Broadway production opened at the Shubert Theater (moving later to the Alvin Theater) on November 29, 1956 and played for 924 performances through March 7, 1959. The musical was nominated for the 1957 Tony Award for Best Musical.

Jeffrey Moss's phone was the brand new Princess model, just introduced by the Bell System in 1959, the same year this movie was filmed.

An alternate take of "The Midas Touch" (music by Jule Styne, lyrics by Betty Comden and Adolph Green), a production number with lead singer Hal Linden, still exists. In the release print, the second half of the musical proceedings gets shunted to the background, being "talked over" by Dean Martin, Frank Gorshin and Bernard West (billed as Bernie West). The center-stage version is available on the DVD from Warner Home Video.

The last musical produced by MGM's "Freed Unit" headed by producer Arthur Freed. He had previously produced such classic musicals as Meet Me in St. Louis (1944), Easter Parade (1948), An American in Paris (1951), Singin' in the Rain (1952), and Gigi (1958). This is also the 13th and final collaboration between Freed and director Vincente Minnelli.

Eddie Foy Jr.'s character, Otto Kreunz, was named Sandor in the original Broadway version. Sandor was also the name of a villain from one of the old serials from the 1930s and '40s, so the name had to be changed for the movie.

In the song "Drop That Name," two of the dozens of names dropped by the party guests are Vincente Minnelli and Arthur Freed - the director and producer of the movie. However, Minnelli's mention predated the movie. It was in the Broadway show.

The posters on the walls of Mike's Lunch Room all all from Broadway plays and musicals from the mid- to late-50's. Some had been or would later be made into films, such as A View from the Bridge (1962), The Boy Friend (1971), Anastasia (1956), Sweet Bird of Youth (1962), and Gypsy (1962).

In an uncredited role, Len Lesser (Charlie Bessemer) is a stranger at the crosswalk when the scenes focus turns to the simple greeting "Hello", the phrase he would become so identified with as Uncle Leo in "Seinfeld".

Gerry Mulligan, who plays the blind date, was actually Judy Holliday's long- term boyfriend.

The jukebox in Mike's Lunch Room is a 1959 Rock-Ola Tempo 1, model 1468ST. It could hold 120 45rpm "single" records.

This film failed at the box office, resulting in a loss to MGM of $1,720,000 ($14.62M in 2018) according to studio records.

In the background of the Times Square scene, a movie theater marquee says "GIGI--opening next week." "Gigi," another MGM musical, actually opened two years before "Bells Are Ringing."

When Ella is packing, on the wall beside her is an illustration of a BOAC Bristol Type 175 "Britannia" flying over lower Manhattan. This was probably a cropped travel poster.