Plot Summary:In 1949, during the Chinese Civil War, British warship H.M.S. Amethyst sails up the Yangtse river but on the return trip finds its way blocked by a barrage fire from the Communist Chinese shore batteries.
While sailing lawfully up the Yangste river in 1949, the British warship Amethyst found its return to the open sea blocked by Communist Chinese shore batteries that unexpectedly opened fire. In charge, Lieutenant Commander Kerans was not however prepared for his crew and his ship to remain as a hostage for the Chinese to use as an international pawn.