Carolyn Keene is a "collective pseudonym" for various writers.
Yesterday, I wrote about Don Pendleton’s The Executioner action adventure series featuring the war machine, Mack Bolan. Pendleton himself wrote fewer than 40 of these racy novels. But, Gold Eagle Worldwide, to whom the creator sold his rights to, has published more than 600 books in the series as well as offshoots—none written by Pendleton, nonetheless attributed to him. They are ghostwritten by a number of very talented writers whose contributions are acknowledged on the copyright page. The covers still belong to Don Pendleton.
The Executioner isn’t the only one to be ghostwritten. Hundreds and thousands of book titles and series have been penned by writers other than the creators themselves. Even good fiction has been ghostwritten, a literary process that is both challenging and lucrative for the nameless writer. For the reader, it means a continuance of his or her favourite series—never mind if the books are no longer authored by the original writers.
So if you are unfamiliar with all the works of your best-loved author, you might be reading a book that’s probably been ghostwritten. You won’t lose the plot, though.