Lover Come Back (1961)

Jerry Webster and Carol Templeton are both in the advertising business, but for different agencies. Annoyed by Jerry's methods of using alcohol and women to ensure contracts for his agency, Carol tries to get him thrown out of his profession. To avoid this Jerry bribes the girl who would testify against him by starring her in a TV commercial for a product named VIP that he's just made up. By accident these commercials are broadcast, and to keep his job, Jerry must come up with VIP for which he enlists the help of Doctor Linus Tyler. Carol goes to see the Doctor to try to get the VIP account, but because she and Jerry have never met, she mistakes Jerry for the Doctor. Jerry takes advantage of this situation to win her.