A world-famous cryptographer has vanished without a trace. She spent years creating an unbreakable security system - and now, in a cruel twist of irony, unlocking that system is the only way to find her. Witness statements from those closest to her reveal someone who was paranoid and very well connected - but what was she hiding ? Then, a secret file marked 'X' is discovered, containing a list of names and 12 cryptic clues . Somewhere among tens of thousands of possible codes lies the one sequence that unlocks the truth - and where she may be. But here's the catch. Each clue reveals the incorrect answers only . Using logic, deduction and a trail of increasingly revealing clues, you'll discard thousands of possibilities , narrow the field and uncover the only code that fits every piece of evidence. With thousands of codes and just 500 words , your only job is to find the correct code.

Can you follow the clues, crack the case and reveal the secret cipher before it's lost forever? Also available : Elimination Mystery Puzzle Book: Find the Fugitives (9781807710668) Elimination Mystery Puzzle Book: Find the Christmas Killer (9781807710644).