In 1949, as the Chinese Civil War was about to enter its final, explosive stage, the small British frigate HMS Amethyst was sent on a dangerous mission up the Yangtze River to protect British citizens in Nanking. En route it was attacked by the Chinese Communists and held hostage on the river for several months before the crew managed to make a daring escape.The 'Amethyst' captured news headlines around the world and became an unlikely symbol of the cold war in Asia. This dramatic...