In the waning days of World War II, Germany, desperate for a last chance to defeat the allied nations, resorted to its remaining armaments and soldiers. The German Navy and the remaining U-Boats joined together for one final desperate operation, known as Operation Seawolf, which was an attack on the United States homeland. Captain Hans Kessler, a veteran submarine commander who served in both World Wars, is summoned to complete a mission and help shift the tide of the battle.