Operation Pacific is a World War II movie made in 1951 and filmed at the Pearl Harbor Naval Station in O'ahu, Hawaii, USA. While fighting the war against the Japanese and commanding the submarine USS Thunderfish, Duke Gifford (John Wayne) comes across his share of troubles. After the death of his commanding officer, John T. "Pop" Perry (Ward Bond), Duke must deal with the grief of losing him and the overwhelming guilt that he could have done something to prevent it. At the same time, he takes personal responsibility of commanding the submarine and fixing the problematic torpedoes that explode too early or never at all. Duke is also determined to win back his ex-wife, a nurse by the name of Mary Stuart (Patricia Neal), and to do so he must go up against his commander's younger brother, Bob Perry (Philip Carey), a navy flier who is also vying for her heart.