The deep sea is the last, vast wilderness on the planet. This is the story of how we imagine, explore and exploit it. For centuries, myth-makers and storytellers have concocted imaginary monsters of the deep, and now scientists are looking there to find bizarre, unknown species, chemicals to make new medicines, and to gain a greater understanding of how this world of ours works. With an average depth of 12,000 feet and chasms that plunge much deeper, it forms a frontier for new discoveries. The Brilliant Abyss tells the story of our relationship with the deep sea - how we imagine, explore and exploit it. It captures the golden age of discovery we are currently in and looks back at the history of how we got here, while also looking forward to the unfolding new environmental disasters that are taking place miles beneath the waves, far beyond the public gaze. Throughout history, there have been two distinct groups of deep-sea explorers. Both have sought knowledge but with different and often conflicting ambitions in mind.

Some people want to quench their curiosity; many more have been lured by the possibilities of commerce and profit. The tension between these two opposing sides is the theme that runs throughout the book, while readers are taken on a chronological journey through humanity's developing relationship with the deep sea. The Brilliant Abyss ends by looking forwards to humanity's advancing impacts on the deep, including mining and pollution and what we can do about them.