Every few seconds, somewhere in the world's oceans, a shark breaks the surface just long enough for a satellite to hear it. A dot appears on a map. And a story begins.

Signals from the Deep follows those dots to their ends ? the true stories of the tagged sharks in this book and the expeditions that track them. You'll meet Mary Lee, the sixteen-foot Cape Cod female who became the most famous shark on the planet; Lydia, the first white shark to cross the Atlantic; Nukumi, the 3,541-pound grandmother; Nicole, the shark that swam from Africa to Australia and back; and Breton, the shark whose track drew a picture of itself.

You'll stand on the pitching deck of a research vessel as a two-ton animal is lifted aboard, measured, tagged, and released in fifteen frantic minutes. You'll follow tiger sharks through Hawaiian reefs, whale sharks across open ocean, and a porbeagle on a 15,000-mile cold-water circuit nobody knew existed until the tags revealed it.

These are adventure stories ? but they're also something rarer: a real-time portrait of an ocean in the middle of becoming something new, and of the scientists, anglers, and coastal towns learning to read it, one ping at a time.

Open the tracker. The dots are moving.