The ocean covers seventy per cent of the surface of our planet, and two thirds of this lie beyond national borders. Owned by all nations and no nation simultaneously, these waters are home to some of the richest and most biodiverse environments on the planet.

But they are also home to exploitation on a scale that few of us can imagine. Here, industry and economic progress rule and lax enforcement and apathy are the status quo. Out of sight and often out of mind, a battle rages to control, profit from, protect, or obliterate the world's largest, wildest commons.

Heffernan sets sail on a journey to uncover the truth behind deeply exploitative fishing practices, investigate the potentially devastating impact of deep-sea mining, and hold to task the Silicon-valley interventionists whose solutions to climate change are often wildly optimistic, radically irresponsible or both. The result is a forceful and deeply researched manifesto calling for the protection and preservation of this final frontier - the last vestiges of wilderness on Earth.