(ABC - Thames TV spy thriller series, 1967-72)

Season 3 Episode 2: Summoned to Appear
A man is being followed. He boards a bus and goes upstairs…..

…..while his shadow sits downstairs. This is not standard London Transport fare, though - I believe from the two rear windows and the folded back rear door that this is a Midland Red BMMO D9; I'd welcome confirmation. Sadly there's no view from outside the bus.