Jack the Ripper

Jack the Ripper, also known as Jolly Jack (TV: The Talons of Weng-Chiang, PROSE: Matrix), Saucy Jack (COMIC: Ripper's Curse), and Leather Apron (PROSE: Matrix) was the name given to a serial killer who brutally murdered prostitutes in London's East End in 1888. Most people agreed that only five murders were canon. (PROSE: Matrix; COMIC: Ripper's Curse)

Potential suspects
There are various conflicting accounts concerning the murderer's identity and his eventual fate.

The Fellowship committed murders, usually women, to summon the Yssgaroth into the universe. William Blake and the Seventh Doctor saw the group's albino leader at a bordello around the time of the murder of Elizabeth Stride, the third victim. All known members were caught in a fire. (PROSE: The Pit)

The Valeyard used the murders to power the Dark Matrix. He created an alternate timeline where the murders continued leading to anarchy in London. Eventually, he killed through his undead wraiths and followers, the Jacksprites. He was defeated by the Seventh Doctor. (PROSE: Matrix)

In post-Time War history the Re'nar war criminal Mac'atyde could be directly connected to the last three murders which he intended to blame on the Ju'wes. His pursuer, "Sir Charles Warren", couldn't stop him until the fifth victim was killed because he already knew what Earth history said about the murders. (COMIC: Ripper's Curse)

Inspector Frederick Abberline apprehended a man he identified as Jack the Ripper but kept it a secret because of his connections to the British Royal Family. Later, the Ripper escaped and Abberline approached Henry Gordon Jago and George Litefoot to help him find the murderer, who at that point used the alias "Carlton". He was employed at the New Regency Theatre. (AUDIO: The Wax Princess)

Jack was believed caught by the Silurian Madame Vastra, who proceeded to devour him. She found him "stringy, but tasty all the same". (TV: A Good Man Goes to War)

Legacy
The London Dungeon had re-enactments of the Jack the Ripper murders to attract tourists. For "one glorious summer", Tamsin Drew played "a Cockney drab who gets done to death by Jack the Ripper". (AUDIO: Deimos)

Other references
The killings of Li H'sen Chang were blamed on Jack the Ripper by some newspapers. (TV: The Talons of Weng-Chiang) After a series of brutal London murders in 1909, some believed that it meant the return of either Jack the Ripper or Spring-heeled Jack. (PROSE: Birthright, AUDIO: Birthright)

The Fifth Doctor planned to investigate the mystery of Jack the Ripper's identity for the use in his book Doctor Who Discovers Historical Mysteries. (AUDIO: The Kingmaker) By his eighth incarnation, he believed that he knew Jack the Ripper's identity. (PROSE: The Bodysnatchers, Interference) Chris Cwej likewise believed that he knew it. (PROSE: Dead Romance)

The architecture of the Torchwood Hub made Owen Harper think that Jack the Ripper should be prowling around somewhere. (PROSE: Slow Decay)