This meant that in order to give us something to test against, I had to trace a direct descendant through the female line of Catherine Eddowes. Luckily, a woman named Karen Miller, the three-times great-granddaughter of Eddowes, had featured in a documentary about the Ripper’s victims, and agreed to provide a sample of her DNA.

Jari managed to get six complete DNA profiles from the shawl, and when he tested them against Karen’s they were a perfect match.

It was an amazing breakthrough. We now knew that the shawl was authentic, and was at the scene of the crime in September 1888, and had the victim’s blood on it. On its own, this made it the single most important artefact in Ripper history: nothing else has ever been linked scientifically to the scene of any of the crimes.

Months of research on the shawl, including analysing the dyes used, had proved that it was made in Eastern Europe in the early 19th Century. Now it was time to attempt to prove that it contained the killer’s DNA.