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)