The author graduates from an elite university and enters the submarine service in the mid-1980s when rhetoric between the US and USSR threatens to turn the Cold War hot. He encounters an unforgiving world where submarines hunt each other unseen and unheralded in the ocean depths and in which minor mistakes can result in catastrophe. On four classified missions to the Mediterranean Sea, the North Atlantic, the Barents Sea, and the North Pole, he gradually and painfully learns the trade of a nuclear submarine officer in a world few people know of and even fewer have experienced.

These missions exert a heavy personal toll. At sea, the submarine crew exercises total radio silence and the rescue buoy is welded fast to the hull, ensuring that their families will never know if a catastrophe occurs. During these missions, his young wife suffers a miscarriage and later gives birth via emergency C-section, all while the author is at sea and unaware. While she undergoes these trials alone, the sub conducts missions vital to the security of the United States. Far from home, in the unforgiving depths, they track adversary submarines in dangerous games of cat and mouse where a mistake could result in a collision, flooding, and death. A storm damages the sub on the way to the North Pole, jeopardizing the ability to surface through the ice. They finally do so, after weeks of transiting through underwater ice canyons of pressure ridges capable of rupturing the hull on impact. While under the ice the crew suffers a poison gas leak and has to find a hole to surface quickly or perish.

The main theme of the work is growth. As the author journeyed to the ends of the earth and the depths of the ocean, he also made a personal journey from a sniveling boy-man to an apex predator of the deep. Sub-themes are how men and women cope with adversity, and how when things are at their worst, people are at their best. It is a tribute to the human spirit, especially the men who sailed these ships, and the families who loved and supported them.