Move to Hollywood
After two years of her radio work, Ruth took Jane to Hollywood before her sixth birthday in 1932 to explore opportunities in film. Walter remained in Atlanta, sending them $100 a month on which to live. In Los Angeles, Jane performed on children's shows on KFWB radio, did cartoon voice-overs, and also modeled. She got her first film role as an extra when their neighbor invited her to come along for her daughter's interview for Handle with Care (1932). Withers stood to the side while the other children interviewed with director David Butler. The assistant director came over and asked her why she was not standing with the others. "Sir, I was not invited to the interview. I came with our friends", she replied. The assistant director told her that Butler had seen her and wanted her to interview as well. Handle with Care was Withers's first film appearance, though she and all the children were photographed with their backs to the camera.
Withers subsequently appeared in many films as an uncredited extra, though occasionally she had a line of dialogue. She stood out from the other girls at auditions because of her appearance: she had a Dutchboy bob and preferred tailored clothes to frilly dresses. "Every interview I ever went on I was the only one with a tailored dress, with straight bangs and straight haircut, and no curls and no frills", she recalled. Butler was the first to notice this about her. He told her, "You're different than any other kid that I've ever seen in Hollywood. You've got a special quality and someday you are going to be a famous little star".
Withers was working as an extra on It's a Gift (1934), when W. C. Fields selected her from a group of juvenile extras to do a pantomime hopscotch scene with him. Afterwards, he praised her timing and called over her mother to compliment her on Jane's talent and predict that she would go far.
Withers's big break came two years after she started working as an extra, when she landed a supporting role in the Shirley Temple film Bright Eyes (also 1934), also directed by Butler. On her interview, Butler asked her if she could imitate a machine gun, and she gave it a try. She also charmed the casting director with her impersonations. Her character, Joy Smythe, is spoiled and obnoxious, a perfect foil for Temple's sweet personality. Withers was concerned that filmgoers would hate her for being so mean to Temple, but the film was a box-office hit. Withers said that director Butler confided to her, "You stole the picture".
Former child star Dickie Moore, in his memoir, wrote that Gertrude Temple was very protective of Shirley. While performing together in the film Bright Eyes with Shirley, Jane was prohibited from speaking to Shirley except in character.
After filming wrapped, Withers signed a seven-year contract with Fox Film Corporation. Included in her contract was the right to choose the crew members who would work on her productions. Her crew, dubbed the "Withers Family", worked on all her subsequent films.
After Withers signed her contract with Fox, her mother invested $10,000 into developing additional skills to improve her versatility as an actress, with the intention of spending $20,000 over an eight-year period. This included "ice skating lessons, voice training, horsemanship, dancing, French, Spanish, and swimming lessons".