On a cold October night, U.S.S. Mako... entered San Diego harbor, battered and brine-stained from her last long patrol."" The itinerary of that last patrol is the subject of this novel as reader and crew submerge into the torpedoed waters of the Pacific during World War II. Having been reduced from a burning ship soon after Pearl Harbor, Keith Stocker decides to join the Navy. After training at New London, Keith is assigned to the Mako along with him favorite enemy, torpedo instructor Herb Jolley. The gap between classroom war and shooting war is bridged quickly -- at Guadalcanal, the Solomon and in the waters between China and Korea. Luck follows the Mako and its crew. They are effective in seriously denting Japan's backyard shipping, they manage to avoid traps and to escape the explosives dumped on them by Japanese destroyers. But their luck runs out half way, when they are finally spotted, the brave skipper killed and the sub attacked mercilessly from above. How they hide away until it is safe to make for clear waters climaxes an exciting portrait of sub warfare and the kinds of skilled professionals and brave beginners who participated.