This is the book that started it all. This is the driving force behind the Bookhouse Institute.

Published: August 1979
Solved: March 1982

Pages: 32
ISBN: 9780224016179
Publisher: Jonathan Cape

Masquerade is a picture book that sparked a treasure hunt by including concealed clues to the location of a jewelled golden hare that had been created and hidden somewhere in Britain. The book became the inspiration for a genre of books known today as armchair treasure hunts.

The book contains fifteen detailed paintings that illustrate the story of a hare named Jack Hare, who is asked to carry a treasure from the Moon to the Sun. On reaching the Sun, Jack finds that he has lost the treasure, and the reader is challenged to discover its location.

Along with creating the book, Williams crafted 18-carat gold and jewels into a large filigree pendant in the shape of a hare. He sealed the hare inside a small ceramic casket, both to protect the prize from soil and to foil attempts to locate the treasure using a metal detector. The casket was inscribed with the legend "I am the keeper of the jewel of Masquerade, which lies waiting safe inside me for you or eternity".