Through dolphins, we can see the best and worst of mankind. On average, seventy four dolphins wash up on the Gulf of Mexico's north shore every year. In the first half of 2012, there were eight hundred and ninety-one of them, with stillborn baby dolphins washing up at ten times the average yearly rate. The cause? BP's disastrous oil spill in 2010. For decades mankind's actions have led to the deaths of thousands of these beautiful creatures and this continues now, at a time when we know more about them than we ever have before. We know about their intelligence, abilities, and their culture. We know how similar to us they really are. In her most provocative book yet, Susan Casey takes us into an underwater world that is similar to our own in ways no other animal's world is. We're at a crossroads now where we could end up destroying these beautiful creatures, and our relationship with nature has become so dysfunctional that it jeopardises our own existence. By combining her own personal narrative with her in-depth scientific research, Casey delivers a narrative which is both compassionate and thrilling.