THE INSTANT NEW YORK TIMES BESTSELLERAn awe-inspiring portrait of the mysterious world beneath the waves, and the men and women who seek to uncover its secrets.

'Masterful and mesmerizing . .

. an irresistible mix of splendid scholarship, heart-stopping adventure writing, and vivid, visceral prose.' Sy Montgomery, author of Soul of an Octopus 'Fantastical and forbidding' Washington Post 'A fascinating history' Time'Casey’s descriptions of the shimmeringly strange life teeming below the wav...