The story takes place off the China Coast in the months before Pearl Harbor. The Chinese Mafia hatch a plot to highjack a barge load of high-grade tungsten ore belonging to the Americans and sell it to the Japanese. Two young Americans are hired to sail an ancient sea-going tugboat from Hong Kong to the Philippines where they pick up the barge and tow it back to Shanghai. Their amorous adventures in the ports, their battles with nature, hostile navies and modern-day pirates make up a good tale, which culminates in a royal battle for the prize in the war-torn harbor of Shanghai.