Meanwhile, she got her first major film break in 1934, when Lilian Harvey abandoned the lead role in a film version of George White's 1935 Scandals, in which Vallee was also to appear. Hired first to perform a musical number with Vallee, Faye ended up as the female lead. And she became a hit with film audiences of the 1930s, particularly when Fox mastermind producer Darryl F. Zanuck made her his protege. He softened Faye from a wisecracking show girl to a youthful, yet somewhat motherly figure such as she played in a few Shirley Temple films.

Faye also received a physical makeover, from being something of a singing version of Jean Harlow to sporting a softer look with a more natural tone to her blonde hair and more mature makeup. This transition was practically a plot point of 1938's Alexander's Ragtime Band, in which Faye's ascent (she plays a singer who moves from barrooms to fame) is dramatized by her increasingly elegant grooming.

Cast in musicals most of all, Faye introduced many popular songs to the hit parade. Considered less than serious as an actress and more than serious as a singer, Faye nailed what many critics consider her best acting performance in 1937's In Old Chicago. She more than held her own - in spite of a mild speech impediment - with co-stars such as Vallee, Al Jolson, Charlotte Greenwood, and Edward Everett Horton, as well as leading men such as Don Ameche, Tyrone Power, and John Payne.

Color film flattered Faye enormously, and she shone in the splashy musical features that were a Fox trademark in the 1940s. She frequently played a performer, often one moving up in society, allowing for situations that ranged from the poignant to the comic. Films such as Weekend in Havana and That Night in Rio (atypically, as a Brazilian aristocrat) made good use of Faye's husky singing voice, solid comic timing, and flair for carrying off the era's starry-eyed romantic storylines. 1943's The Gang's All Here is perhaps the epitome of these films, with lavish production values and a range of supporting players (including the memorable Carmen Miranda in the indescribable "Lady in the Tutti-Frutti Hat" number) that camouflage the film's trivial plot and leisurely pacing.

In 1943, after taking a year off to have her first daughter, Faye starred in the Technicolor musical Hello, Frisco, Hello. It was in this film that she sang her trademark song, "You'll Never Know". Released at the height of World War II, the film became one of Faye's personal favorites and one of her highest-grossing pictures for Fox.

Faye's career continued until 1944 when she was cast in Fallen Angel. whose title became only too telling, as circumstances turned out. Designed ostensibly as Faye's vehicle, the film all but became her celluloid epitaph when Zanuck, trying to build his new protege Linda Darnell, ordered many Faye scenes cut and Darnell emphasized. When Faye saw a screening of the final product, she drove away from the Fox studio refusing to return, feeling she had been undercut deliberately by Zanuck.

Zanuck hit back, it is said, by having Faye blackballed for breach of contract, effectively ending her film career. Released in 1945, Fallen Angel was Faye's last film as a major Hollywood star.

But seventeen years after the Fallen Angel debacle, Faye went before the cameras again, in 1962's State Fair. While Faye received good reviews, the film was not a great success, and she made only infrequent cameo appearances in films thereafter.