The blue deep

In May 1954, French rule in Indochina is nearly finished. All that stands between the Viet Minh and Hanoi is the French fortress at Dien Bien Phu. Hanoi is a city of intrigue. A group of American flight instructors, led by Major Marsh McCall, are in Hanoi ostensibly to train French helicopter pilots. But their covert mission is to expose black marketeers operating in the area.