Interestingly I recently saw an old movie.
As a sucker for Sherlock Holmes movies I gave it a look.
It has Holmes and Watson investigating the Jack the Ripper murders.
And Holmes uncovers a familiar conspiracy of silence on the part of secret societies.
Worth a watch if you have the time.
Murder by Decree (1979)
https://www.imdb.com/title/tt0079592/?ref_=nv_sr_srsg_0