A dramatic story of the Battle of the Atlantic, where the heroes are the men, the heroines are the ships they sail in, and the villain is the cruel sea. On board H.M.S. Compass Rose, an escort ship, is one professional seaman. The others are civilians turned into wartime sailors; men not trained for the rigors and horrors of war. But as the task of keeping open the Atlantic life-line becomes more and more hazardous, so the men are thrown together, hardened and wiser, in companionship. Then the ship is torpedoed. But for the survivors, the greatest fight is only just beginning.