Sorry, Wrong Number is a play written by Lucille Fletcher in 1952. The main character is Mrs. Stevenson, an invalid, who has been attempting to get in touch with her husband, who is working late. However, the line is busy, and she ends up overhearing a phone conversation between a killer named George and his boss. They are discussing the specifics of a pending murder of a woman at 11:15 p.m. that same night.

Mrs. Stevenson attempts to get the call traced. The operator urges her to contact the police, which she does. The police can only say they will check into things. Mrs. Stevenson then learns that her husband will not be home that evening. She realizes that she is the intended murder victim. She desperately tries to get back in touch with the police, but she is too late. The murderer is already in the house and listening in on the call. Just before she is connected to the police, Mrs. Stevenson is murdered.