A fair amount of the early action takes place inside the old terminal building at Kai Tak airport as a smuggled diamond is passed around from one person to another inside a bar of soap. As a result we get some shots of what I can only assume is the inside of the old terminal building as well as a few shots of the exterior including the first one, below, of the ramp up to the departures area.
A few shots of the interior which look legit to me, although feel free to correct me otherwise.
And finally a couple more shots on the outside showing the famous (and still there) runway. Note in the top picture you can see the buildings that line Mok Cheong Street (aka Saw Mill Street) in Ma Tau Wai. Those buildings were all completed in and around 1960 and are still standing.