"Peter Lawrence" wrote

I notice that the Pentonville Road station was Kings Cross St Pancras in
the video - later it became just Kings Cross (to avoid confusion with the
main LU station?)

Until the 1930s the Met/Circle platforms were alongside the ones used by
Midland and Great Northern trains to Moorgate via the Widened Lines and the
whole station was operated by the Met/LPTB. When the Circle/Met decamped to
their new platforms, the Widened Lines station was still operated by LPTB/LT
and named Kings Cross St Pancras as part of the Underground station. In 1976
the Great Northern trains decamped as part of GN electrics, and started
going to Moorgate via the Northern City line. This left just a handful of
trains to/from the Midland, and the station was renamed Kings Cross LT (so
passengers didn't start looking for these trains at St Pancras). Later the
line was closed for the BedPan electrification, and when it reopened it was
named Kings Cross Midland City (and operated by the LM Region, then Network
SouthEast. It was renamed Kings Cross Thameslink when Thameslink opened.

Peter