Came across an article about Josef on the All That’s Interesting website.
It’s actually pretty good (all things considered) that summarizes the story of Josef quite well.
They reference my interview with the RadioTimes back in 2012, and this seems to be their primary resource.
There are only a few minor errors:
- Josef was arrested in 1938 (not 1939)
- he fired his pistol (not his revolver – although this is a forgivable error since even the MI5 files use the two terms interchangeably).