Introduction: Van Leeuwenhoek decides to look (New tools plus inquisitive humans equals unexpected discovery) -- Enter, pursued by a whale (The twenty-first-century revolution in cetacean biology, and how I joined it) -- A song in the ocean (How we saved the whales by decoding them) -- The law of the tongue (Different species already communicate) -- The joy of whales (Do cetaceans have the tools to talk and listen?) -- "Some sort of stupid, big fish" (What can whale brains tell us about their minds?) -- The search for an animal language (Let's avoid the word "language") -- Deep minds: cetacean culture club (How dolphin behaviors suggest they're worth trying to chat to) -- The sea has ears (Robots can record whale communications we never could before) -- Animalgorithms (How we can train machines to find patterns in cetacean communications) -- Machines of loving grace (Google translate for whales) -- Anthropodenial (Humans underestimate other animals...and why it matters) -- Dances with whales (It's time to find out if we can speak whale).