The Kid Sister (1945)

Joan Hollingsworth is Ethel's younger sister, and their mother believes that Ethel is entitled to all the advantages until she acquires a husband, but Joan thinks otherwise. Forbidden to attend a family dinner given for socialite J. Waldo Barnes, the latest entry in the matrimonial sweepstakes, Joan poses as the family maid in receiving the guests. When her mother discovers her ruse, Joan sneaks out of the house and accepts a ride from a man, a burglar casing the house who thinks Joan is one of the gang. The car is wrecked and Joan escapes on foot, but is overtaken on the grounds of a large estate by motorcycle policeman Michael who accepts her story of being a maid on the estate. Her impersonation is aided by the nearsighted housekeeper, Mrs. Wiggins, who orders her to her room. Inside the mansion, Joan is trapped when the owner returns--and decides she is a female "Raffles" who is in need of reform.