(ITV drama, 2000)

Dramatisation of the love affair between actors Sidney James and Barbara Windsor, set against the filming of the 'Carry On' films in the 1960s and 1970s.
Two dining buses feature, but most seen is a Bristol VRTSL, downstairs…..

……..and upstairs:

The registration plate is never seen in its entirety, and I've not been able to trace it:

The other bus is barely seen until it leaves the filming site. It appears to be STD121L, a Leyland Leopard PSU4B/2R with Pennine body new in 1973 to Lancaster City Transport, which went on to be a dining bus:

For good measure there's also a quick view of a passing Royal Blue Bristol MW6G: