Are you smarter than a Singaporean ten-year-old?Can you beat Sherlock Holmes?If you think the answer is yes - I challenge you to solve my problems.Here are 125 of the world's best brainteasers from the last two millennia, taking us from ancient China to medieval Europe, Victorian England to modern-day Japan, with stories of espionage, mathematical breakthroughs and puzzling rivalries along the way. Pit your wits against logic puzzles and kinship riddles, pangrams and river-crossing conundrums.Some solutions rely on a touch of cunning, others call for creativity, others need mercilessly logical thought.Some can only be solved be 2 per cent of the population.All are guaranteed to sharpen your mind. Let's get puzzling!