A unique book of puzzles from British intelligence organisation GCHQ.
GCHQ (Government Communications Headquarters) is a signals intelligence and cyber security organisation whose mission is to keep Britain safe from terror attacks and cybercrime.
A fiendish work, as frustrating, divisive and annoying as it is
deeply fulfilling: the true spirit of Christmas * Guardian
Surely the trickiest puzzle book in years. Crack these fiendish problems and Trivial Pursuit should be a doddle * Daily Telegraph *
Ideal for the crossword enthusiast * Daily Telegraph *
An explosion of a puzzle collection, too, with hundreds of questions and loads of peripheral material, including captioned photographs and history of twentieth-century British encryption, featuring the work of Alan Turing * The Times Literary Supplement *
This isn't your grandfather's Sudoku book. Rather, it's a puzzle compendium put together by the organisation that made the Bletchley Park breakthroughs - quizzes, bewilderments and brainteasers to challenge even the sharpest of minds * The Gentleman's Journal *
WINNER OF STOCKING FILLER OF THE YEAR AWARD * THE GUARDIAN *