This premiered theatrically in the UK in March 1981 and was the main Christmas Day movie on the BBC that December. At a time when the theatrical window between cinema debut and TV broadcast was 3-5 years, this was highly irregular.
The "bank" exterior is Unilever House, 100 Victoria Embankment, London.
The make and model of the truck seen in the movie was a yellow 1967 Morris FM van.
Actress Julie Christie turned down the role of Dinah Booker which in the end was cast with Susannah York.