Naval warfare
The book also focuses on the intense combat between the "Keeling" and multiple U-boats, with the "Keeling" eventually racking up multiple kills, and on the ship's daring rescue missions as the convoy increasingly falls prey to the U-boats, all in a race against time to escape the undefended stretches of the Atlantic. The book is a rich, detailed accounting of Naval warfare, ship handling, and the inner logic of an experienced officer wrestling with the many minute judgments necessary to maintain rigid discipline during conditions of relentless tedium punctuated with extreme danger.