It's 1943 and World War II rages on. Coast Guard Captain Josh Thurlow is on hand at the invasion of Tarawa, as the U.S. Navy begins the grand strategy of throwing her marines at island after bloody island across the Pacific. But the young Americans go up against fanatical defenders, who revel in snipers, big guns, and human wave attacks from which there is no escape save death. Critically wounded, Josh expects to die. Instead, Sister Mary Kathleen, a young Irish nun, nurses him back to health, then shanghais Josh, sidekick Bosun Ready O'Neal, and three marines to a group of beautiful tropical islands invaded by a brutal Japanese warlord. Josh and his little band must decide whether to help the Sister fight the battle she demands, return to Tarawa and the "real" war, or settle down in the romantic splendor of the South Seas.