This odd series in which characters from Z-Cars retrospectively investigate the Whitechapel Murders is heading for DVD: https://smile.amazon.co.uk/Jack-Ripper-Complete-BBC-DVD/dp/B07Y1W1F4Q/ref=pd_sbs_74_5/260-2135154-9827929?_encoding=UTF8&pd_rd_i=B07Y1W1F4Q&pd_rd_r=5049ef9d-509c-4aac-bed8-107fd6812868&pd_rd_w=2oGtp&pd_rd_wg=4sJTa&pf_rd_p=2b420a2f-6593-478e-8b5f-cb43865ff16f&pf_rd_r=NR5YTD4H4BVH7HCAQQ6X&psc=1&refRID=NR5YTD4H4BVH7HCAQQ6X
I have a very vague memory of having seen at least part of the series as it's the first time I was aware of the supposed Royal theory. Can't remember if it's any good though.