The Puzzler's Dilemma explores the world of classic logic puzzles, and tells the amazing stories behind them, from the Lighthouse of Alexandria to code-breaking with the Enigma machine. Here are brain teasers that even maths whizzes have never seen explained by a mind as nimble and playful as Derrick Niederman's, the author of Number Freak and the New York Times's near-genius crossword setter. A man is found dead in a room, hanging from a rope with only a puddle of water beneath him: What happened? Just the thing to get your brain working at full speed!