The Merlin Mystery is a 1998 puzzle/children's book, written by Jonathan Gunson and illustrated by Gunson and Marten Coombe. Published by Warner Books and certified by Mensa, it served as an armchair treasure hunt book, challenging its readers to solve the titular mystery by deciphering the pictures to learn how to cast a magic spell, the details of which were to be drawn and sent to an official addess. None of the 30,000 entries received contained the correct solution, so the £75,000 prize was donated to the World Wildlife Fund.
