User blog comment:Master Sima Yi/Assassinews 31-03-'15 — Assassin's Creed Chronicles announcement trailer/@comment-206.176.80.254-20150509224341/@comment-1888015-20150512031846

In regards to Jack the Ripper, I do actually like the idea of "unsolveable Murder Mysteries" or sidemissions involving midnight/late night disturbances with chase sequences.

So, you may never catch Jack the Ripper, but at the final mission, after the final chase, they'll leave something behind that gives the protagonist (but not necessarily you) the impression that they know who it is, and also a weapon perhaps for use, or a customization piece such as a mask or a cloth to tie around your face, similar to the Night Stalker character's mask.