The Train is two different movies - one (composed of the brilliant opening and closing scenes) debates the value of art, while the other (consisting of the action-packed middle portions) is concerned with the technical details of sabotaging Nazi efforts to steal France's art. I'd like to remember the film more for the excellent elements of its bookends than the only occasionally-exciting body, but it's ultimately an inconsistent work by a proficient director who has achieved greater things.
The film opens in Paris during the last days of the German occupation, where Nazi Col. Von Waldheim (Paul Scofield) discusses the art curated by Mademoiselle Villard (Suzanne Flon) at the Jeu de Paume Museum. Villard commends him for recognizing the priceless nature of the art and being more sophisticated than the average Nazi. While he accepts the compliments, he tells her that the paintings have monetary value and will be shipped to Berlin to contribute to Germany's war chest. Shocked, she takes the information to the French Underground led by Labiche (Burt Lancaster) , who discuss whether France's artistic heritage is worth lives. After many dramatic acts of sabotage and courage, the discussion is resumed between Von Waldheim and Labiche.