"The Famous Five and the Pink Pearls" (first published by Knight Books in 1987; later republished by Hodder and Stoughton in 1994 as "The Five and the Pink Pearls")

In 1996, a book written by Claude Voilier and illustrated by Anne Bozellec, entitled "Les Cinq et le secret du vieux puits" ("The Five and the Secret of the Old Well"), was published and may constitute the 25th volume in the series.However, from the rather scant information available about the book, it appears as though it may be little more than a rewrite or updated translation of "Le Club des Cinq et le vieux puits", which is the French version of "Five Have a Mystery to Solve", the 20th book in Enid Blyton's original The Famous Five series.