"Night Nurse" (1931) A Warner Brothers - William A Wellman Photoplay

Lora Hart applies for a job as a nurse trainee but is rejected when the hospital's superintendent of nurses, Miss Dillon, learns she does not have a high school diploma. After a chance encounter with the hospital's chief of staff, Dr. Arthur Bell, Hart charms him and he tells Dillon to hire her.

Lora and Miss Maloney, a fellow nurse, become roommates and best friends. After they violate curfew, Miss Dillon assigns them night duty in the emergency room. When Lora treats a bootlegger named Mortie for a gunshot wound, he persuades her to not report the wound to the police as required by law. He wants to know Lora better, but she resists him at first.

After she passes her training, Lora is hired as a private nurse for two sick children, Desney and Nanny Ritchey. She moves into the Ritchey mansion, site of frequent parties. Mrs. Ritchey, the children's socialite mother, lives in an alcoholic stupor and is infatuated with her brutish chauffeur Nick. When a drunken guest tries to molest Lora, Nick knocks him out. After Mrs. Ritchey gets soused, Nick demands that Lora pump her stomach; when she refuses, he knocks her unconscious with a telephone receiver.

The Ritchey family physician is "society doctor" and drug addict Milton Ranger. Lora is alarmed by Dr. Ranger's treatment of the children after she sees that they are being starved to death. When she is unable to persuade anyone to take her seriously, she quits and tells Dr. Bell of her suspicions. At first, he is reluctant to interfere with another doctor's patients, but eventually he advises her to return to her job to gather evidence of the children's mistreatment.

Nanny becomes so weak that Lora fears she will die. Lora is unable to get Mrs. Ritchey to show any concern. When Mortie delivers liquor to the perpetual party at the mansion, Lora sends him to get milk. He steals some from a delicatessen to allow Lora to give Nanny a milk bath, a folk remedy recommended by Mrs. Maxwell, the frightened housekeeper.

Maxwell gets drunk and confides her suspicions to Lora. Nanny and Desney have a trust fund from their late father. Nick killed their sister with his car; with Dr. Ranger's help, he is deliberately starving the girls. With their deaths, the trust fund would go to Mrs. Ritchey, and Nick plans to marry her for the money.

After being threatened by Mortie, Dr. Bell arrives and examines Nanny. When he tries to take her to the hospital, however, Nick knocks him out. Mortie stops Nick from interfering further, and Nanny's life is saved when Lora provides her an emergency blood transfusion.

The next day, Mortie gives Lora a lift in his car. When they pass several police cars, Mortie tells Lora that Nick will not be arrested because he told his criminal associates of his dislike for him. An ambulance delivers a corpse dressed in a chauffeur's uniform to the hospital's morgue.