The Five have heard about Demon Rocks, but they were just stories and now they go to investigate to find out the truth. When the find a very old, valuable, gold coin, they start examining and looking into it harder and more carefully to solve the mystery but someone else is there determined to get to the bottom of the crisis! Caution! This book is not suitable for dull, tedious, boring, killjoy people but fun, cool and happy people will be able to enjoy it. I would rate this book six out ten but I did like most of the beginning.