By mistake Nancy Drew receives a letter from England intended for an heiress, also named Nancy Drew. When Nancy undertakes a search for the missing young woman, it becomes obvious that a ruthless, dangerous man is determined to prevent her from finding the heiress or himself. Clues that Nancy unearths lead her to believe that the villainous Edgar Nixon plans to marry the heiress and then steal her inheritance.

Carolyn Keene is a pen name used by a variety of authors for the classic Nancy Drew Mystery series. The first author to use the pseudonym was Mildred Wirt Benson, who wrote 23 of the original 30 books. Other writers who have adapted the "Carolyn Keene" moniker include Leslie McFarlane, James Duncan Lawrence, Walter Karig, and Nancy Axelrod.