I'm very mixed about this book, in a lot of ways it is well worth the read and I do give this a recommendation, the first and last thirds of the story are where it shines the most; you have the foreboding beginning that leads into the horrific alternate London of the 60s where something malevolent and supernatural has caused the UK to collapse into dread and despair over the last century, all stemming from the infamous Jack the Ripper. When the Doctor and Ace go to investigate the Doctor quickly falls under an evil influence and hints that he may in fact be Jack the Ripper.

This then leads into the middle portion and boy is this where the momentum crashes and burns, it's a very overly long and drawn out middle act where Ace wanders from place to place, slowly coming under the influence of the Cheetah virus while the Doctor has lost his memory for what feels like the fiftieth bloody time and is taken in by a kindly old Jewish man. Which leads to a very bizarre inclusion where despite not outright saying it, the story very unsubtley indicates the old man may in fact be the legendary Wandering Jew. If you thought it was bizarre having the Doctor help create the Star of Bethlehem or David Tennant claim to have witnessed the birth of Jesus in Voyage of the Damned, how about this story telling us that the Wandering Jew (a man who according to legend mocked Christ on the way to his crucifixion and was cursed to wander the Earth until the second coming) is in fact real! And it's not like he's an alien or had something sci-fi done to him, he just....is. It's really odd.

The middle portion isn't bad exactly, it sets our heroes on their journeys where they have to overcome their personal demons (mainly Ace), but it certainly could've been a lot shorter as it's mostly just showcasing how rubbish Victorian London was which we've already gathered from many depictions in TV and books in our lives.

It does get going again when we reach the final part and the reveal of Jack the Ripper's identity, which is a great reveal that I sadly ruined for myself as I bought this book specifically because of the Valeyard's involvement. It makes for a great battle between him and the Doctor as he's discovered an ancient Gallifreyan secret in the matrix itself that is a perfect reflection of who he is. In fact the conflict between him and the Doctor is so captivating that Ace just feels more like an afterthought, her whole deal of resisting the Cheetah virus doesn't even come into play.

Maybe when I revisit this I may appreciate the story in its entirety a lot more and may reevaluate my scoring, I think it's altogether decent, it has a strong opening and ending but the middle portion was a slog to get through  and really hampered my enjoyment of the story. But I recommend it for readers