After Nader and Avalon find a recently murdered girl in their Italian hotel room, they quickly scarper out the back entrance and into the hands of British Intelligence. The small alleyway they run down is actually a narrow link between Kennedy Road and MacDonnell Road and pops out onto Kennedy Road not far from the location of this earlier post.
The road on the left is a small road that runs up behind Kennedy Apartments at 34a Kennedy Road (and leads to South Garden Mansion) and the brick wall at the back is a retaining wall for the ground floor carpark/terrace of a development called Seaview Mansion. here is a modern view courtesy of Streetview.
The vegetation on the left is obscuring the wall of Kennedy Apartments but judging from other pictures I've seen the wall remains the same except for glass bricks being put in the wall openings. I also get the impression that the pathway has been widened. Looking at the modern picture you can still see the slanted stone steps on the left side of the path and the right hand side looking much more level. I think this portion of the steps, added where the concrete block with drainage holes is on film, was probably created when the neighbouring section was redeveloped into its current building, Kenville (built 1973). Actually, most of the buildings along this section of Kennedy Road seem to date from the 1960's with the exception of the relative "new boy" just mentioned.