A sober, daytime, conventionally structured narrative about exploring the deep by manned submersible, made personal by Casey’s quest to descend to the depths herself.

Casey’s most sprawling and ambitious book.

Casey’s story is irresistibly personal.

Not just a knowledgeable guide, Ms. Casey is also a memorable wordsmith.

Casey immerses the reader in the science and history of deep-sea exploration.

Zips as enthrallingly along as the state-of-the-art submersibles in which journalist Susan Casey deep-sea dives.

Fascinating.