Which of the following films is a documentary about a London, Midland, and Scottish Railway mail train: Night Mail or What Would Jesus Buy?
Night Mail: Night Mail is a 1936 documentary film about a London, Midland and Scottish Railway (LMS) mail train from London to Scotland, produced by the GPO Film Unit. What Would Jesus Buy?: What Would Jesus Buy? What Would Jesus Buy?:  is a 2007 documentary film produced by Morgan Spurlock and directed by Rob VanAlkemade.
Night Mail