In May 1940 a packed train takes refugees from a French village near the Belgian border fleeing advancing German forces.
The passengers include Julien, a short-sighted radio repairer, his daughter and pregnant wife.
As his half of the train slowly continues across war-torn France, sometimes bombed and strafed by German aircraft, he and the silent woman gradually become intimate and eventually lovers.
He learns that she is a German named Anna, that she is Jewish and that her husband was taken by the Nazis two years ago.
A Jewish woman in the Resistance has been captured with false papers issued in La Rochelle in the name of his wife.