One Night... a Train

In Belgium in 1968, the linguistics professor Mathias (Yves Montand) teaches at a university where the students argue over Flemish nationalism, and he lives with Anne (Anouk Aimée), a French woman. Their relationship has grown strained, and the difference in their languages hangs over it. On a train ride Anne vanishes, and Mathias gets off to search for her in a city he does not know. André Delvaux adapts Johan Daisne's novel and leaves Mathias to wander it.