Le Captif (1962)

Original title: Le captif

Two gun runners, Le Doc and Rougier, save and tend the only survivor of a plane crash into the Vietnamese jungle. When they realize the man named Hamelin is a renowned electronics engineer, they decide to keep him hostage and to release him in exchange for a high ransom. Things get complicated with the coming of Sylvie, Hamelin's wife in search of her missing husband. To make matters worse, Wong,a Chinese gang leader and former ally of the traffickers, turns against them and attacks them with his men.