Kurt Muller, a German engineer, returns to the US with his American-born wife Sara and their three children after 17 years in Europe, where he fought against the Nazi threat. However, his past catches up with him when a Romanian count, Teck de Brancovis, discovers his secret and threatens to expose him to the German embassy.
Watch on the Rhine
A family's road trip takes an unexpected detour when they meet a captivating and mysterious Romanian aristocrat, whose encounter forever changes their lives.