Without explanation, William "Still" Waters, the head of a London business, asks stenographer Monica Trant to be his "official fiancée" for 500 pounds. Monica agrees, in order to help support her brother. Monica is introduced to Waters' family at his home. She charms his mother and other relatives, and even wins over the reserved Waters, but she soon resents the business nature of their proposition and returns to London. Waters then explains the reason for the strange request: A foreign business client had selected him for the husband of his daughter and in order to secure the business deal Waters thought a prior engagement was the easiest way out. Monica forgives him and agrees to be his fiancée in earnest.