Some interesting and very extensive footage within the programme, all filmed
at Marylebone - presumably on a day when the station was closed due to
engineering works, as there were large numbers of extras used in the
evacuation scenes.

The usual amusing inaccuracies, for those of us 'in the know', however -
although the station was never identified by name. Announcements early on in
the episode about trains stopping at Clapham Junction, then later on a
reference to trains from Reading and Ealing Broadway!