After a talent scout spotted her with the Long Beach Players, she signed a contract with Goldwyn studios, for which she made her cinematic debut. In 1937, Day debuted on screen in a bit part in "Stella Dallas". Her contract was dropped shortly thereafter because she "lacked talent". Shortly afterwards, she won lead roles at RKO Pictures in several George O'Brien westerns, in which she was billed as Laraine Johnson. In 1938, she adopted the name "Laraine Day" to honor her previous playhouse manager Elias Day, from whom she had received much of her training. During that time, she was active in establishing a playhouse in Los Angeles for Mormon actors. Ray Bradbury joined for a period of time in 1939, and she let him do some stage prop work and publicity.