(BBC comedy, 1989)

A one-off pilot obscure enough to have escaped the IMDB, this starred Enn Reitel and the rather better-known Liza Goddard.
The opening scenes feature that old chestnut where our hero helps an old lady get on the bus, only to be stopped from boarding himself by the conductor because the bus is now full. Inevitably it's a Routemaster, albeit unidentified: