Full of magical code-breaking skills, non-stop action and a tech-savvy hero, this action-packed adventure is perfect for fans of Percy Jackson, Doctor Who and Alex Rider.

Code breaking genius William Wenton is celebrating his thirteenth birthday when news breaks that Big Ben has suddenly stopped working. This is the first clue in a series of puzzles and codes that will lead William to a network of long-lost underground tunnels beneath London, in pursuit of an ancient weapon of untold power. Secrets, danger and code-cracking abound in this thrilling fantasy-adventure that will push William's skills to the limit.