Thau argues that three puzzles that has exercised some of the best minds in philosophy of language and mind, i.e., Frege's Puzzle, The Inverted Spectrum, and the Knowledge Argument, are, despite appearances, variants of the same puzzle. This is exciting stuff. Many writers on these topics have given different kinds of solutions to these puzzles. If Thau is right, then many will have to simply go back to the drawing board. The prose is clear and jargon free making the book a pleasure to read. This is perhaps the most important book in philosophy of language in mind in the last twenty years.