In April 1945, a U.S. bombardment of the Japanese-held island Okinawa rapidly escalated into the most intense battle of the Pacific. Discover the secret weapon that made American victory possible, and significantly shortened the entire war. Find out how the allied code-breakers gained access to Japan's most confidential battle plans-- even before Pearl Harbor. Experience the fiercest battles leading up to Okinawa. See why events at Okinawa led to the first use of the atomic bomb.