Bitter Victory

Bitter Victory French title Amre victoire is a 1957 black and white FrancoAmerican international coproduction film, shot in CinemaScope and directed by Nicholas Ray. Set in World War II, it stars Richard Burton and Curd Jrgens as two British Army officers sent out on a commando raid in North Africa. Ruth Roman plays the former lover of one and the wife of the other. It is based on the novel of the same name by Ren Hardy.

Major Brands wife Jane is an RAF Flight Lieutenant who enlisted to be near her husband. When Brand invites Leith to drinks with his wife, he picks up the fact that the two had previously had an affair before she married Brand. Leith had walked out on her without explanation.The unit parachutes behind enemy lines with the mission of attacking a German headquarters and bringing back secret plans from a safe to be opened by Wilkins, an experienced safecracker. Dressed as local civilians, Brands hand shakes with fright when he has to knife a German sentry the deed is done by Leith. ........

Source: Wikipedia