There is a documentary that was made in South Africa in 1998. It is called "A Question of Madness". I’ve only seen a tiny clip from this documentary. But you can’t otherwise find anything about it. The tiny clip shows some extremely interesting stuff that I’ve never seen in South Africa before. It also contains the only interview with the assassin Tsafendas. They interviewed him twice.
If anyone ever comes across a copy of this documentary, I would be most interested in it. It is definitely unique and they had access to all kinds of things you normally never get to see.
I suspect that copyright issues are the reason it’s not on the Internet.