Abbots Mead, the disused Victorian house (referred to in the film by its real name) where Marlow takes Jonathan after he has kidnapped him, was bought by film director Stanley Kubrick shortly after this film was made. He and his family lived there from 1965-1979 and he edited many of his films, such as A Clockwork Orange, in an outbuilding alongside the house.
The year this film was released, Robert Shaw played one of the most iconic Bond villains.
Anthony Chester's house is given as 14 Winnington Road, N2. Unusually, not only is this a real address, but some exterior shots were filmed in that road.
The majority of scenes outside Chester's house were filmed at No. 91, whilst when D.I. Parnell first arrives at the road, he turns off the A1 into the north end of the road - the opposite end to the house - and parks there.
John Gregson had previously played a London-based police officer in the film "The Frightened City."