[1]: 29 Arriving in California alongside Mary Healy and Dorris Bowdon in February 1938, Darnell initially was rejected by film studios and was sent home because she was declared "too young."
Although originally wanting to become an actress on the stage, Darnell was featured in a Gateway to Hollywood talent search and initially landed a contract at RKO Pictures.
In an interview during production of Hotel for Women, which lasted until June, Darnell admitted that movie making was not what she expected: "I'm learning what really hard work is.
At home in Dallas I used to sprawl on the lawn and dream about the nice, easy time the screen stars must be having in Hollywood, but the last two months have taught me quite another story.
[11] The film was hailed as one of the "most original entertainment idea[s] in years" and boosted Darnell's popularity, who was nicknamed "Hollywood's loveliest and most exciting star".
[1]: 55 Darnell and Power were cast together for the second time owing to the box office success of Day-Time Wife, and they became a highly publicized onscreen couple, which prompted Darryl F. Zanuck to add 18 more romantic scenes to Brigham Young.
"[14] In the summer of 1940, Darnell began working on The Mark of Zorro (1940), in which she again co-starred as Power's sweetheart in a role for which Anne Baxter was previously considered.
[1]: 58 A big-budget adventure film that was raved over by the critics, The Mark of Zorro was a box office sensation and did much to enhance Darnell's star status.
In late 1940, Fox chose her for the main role in Song of the Islands (1942), a Hawaiian musical film which eventually starred Betty Grable.
Matters changed when she was named one of the four most beautiful women in Hollywood along with Hedy Lamarr, Ingrid Bergman, and Gene Tierney in a 1944 edition of Look.
[1]: 83 Darnell complained that the studio lacked recognition of her, which prodded Zanuck to cast her in Hangover Square (1945), wherein she played a role she personally had chosen.
Despite suffering from the "terrifying" director Otto Preminger, Darnell completed the film and was praised by reviewers so widely that there was even talk of an Oscar nomination.
[18] Although she looked forward to the film project, believing it would be her most important to date,[1]: 90 she was later replaced by newcomer Jean Peters owing to scheduling conflicts, a decision she resented.
During the release of the latter, she was on location in Monument Valley for the filming of the John Ford Western My Darling Clementine (1946), playing a role for which she lost 12 pounds.
[19] In 1946, Darnell won the starring role in the highly anticipated movie Forever Amber, based on a bestselling historical novel that was denounced as being immoral at that time.
"[1]: 98 The search for the actress to portray Amber, a beauty who uses men to make her fortune in 17th century England, was modeled on the extensive process that led to the casting of Vivien Leigh as Scarlett O'Hara.
[1]: 99 Darnell worked long hours at the studio during filming, and according to her older sister she started loathing Preminger, which did not ease production.
She longed for the leading role in the controversial film Pinky (1949), but Zanuck feared that her character would be compared to Amber by the audience, and A Letter to Three Wives co-star Jeanne Crain was cast instead.
She was cast opposite Richard Widmark and Veronica Lake in Slattery's Hurricane (1949), which she perceived as a step down from the level she had reached with A Letter to Three Wives, though it did well at the box office.
Aside from her co-starring role opposite Richard Widmark, Stephen McNally and Sidney Poitier in the noir No Way Out (1950), directed by Joseph L. Mankiewicz, which she later called "the only good picture I ever made," her later films were rarely noteworthy, and her appearances were increasingly sporadic.
Due to her allergy to horses, she loathed making Westerns, and in addition to her complaints about her "colorless" role, she disliked her co-stars Joseph Cotten and Cornel Wilde.
Shortly after its release, she was put on suspension for refusing a role in the film The Guy Who Came Back (1951) opposite Paul Douglas and Joan Bennett because it felt "too similar."
[1]: 146 In 1958, Darnell appeared in the episode "Kid on a Calico Horse" of NBC's Cimarron City along with a cast of other guest stars, including Edgar Buchanan.
[citation needed] In 1940, during the shooting of Star Dust, Darnell for a short time dated teen idol Mickey Rooney.
[1]: 62 Starting at age 17, Darnell dated her publicity agent, Alan Gordon, whom she allegedly married in a double wedding with Lana Turner and Joseph Stephen Crane on July 17, 1942.
"[1]: 54 Most friends and relatives, including her parents, and 20th Century-Fox disapproved of the marriage, and Darnell was believed to look at Marley more as a father figure than as a romantic interest.
Although she initially disavowed gossip regarding an affair, she fell in love with the womanizing millionaire and separated from Marley shortly after finishing My Darling Clementine.
Though she called him the "great love of her life," Mankiewicz never acknowledged the affair; he only mentioned her to his biographer as a "marvelous girl with very terrifying personal problems.
A coroner's inquest ruled that Darnell's death was accidental and that the fire had begun in or near the living-room sofa and was caused by careless smoking; both adult women were smokers.
After the remains had been in storage for ten years, her daughter asked that they be interred at the Union Hill Cemetery, Chester County, Pennsylvania, in the family plot of her son-in-law.