The second book in the series is not much better. It might even be worse than the first book.
I do not have much knowledge about London in time of Charles II, nor of London in general (well, a bit more than the "common" German, but far from any Londoner or historian), but even I was struck by a few things that made me research the situations a bit, and then cringe inwardly. The one that I found most annoying was situating Bedlam directly next to (or in the same building as) Brideswell prison. Then there was all the muddled Alchemy stuff, and the Gog and Magog thing. But there are so many more I did not know about, it is staggering.
Of course, there is a disclaimer at the beginning of the book: "This is a work of fiction. Names, characters, organizations, places, events, and incidents are either products of the author's imagination or are used fictitiously." However, I think that is a poor excuse. Yes, of course this is fiction, but it aims at being historical fiction, and as such it should have certain (research) standards. And not go and say "hey, sorry that things are not realistic, or would be plain wrong, but you know what? - it's all just make-believe anyway, so I can save myself a lot of grief and additional work, and just do as I please".
Unfortunately, that is not why I think this book is worse than the first. In the first novel, there were a lot of coincidences and favourable turns of events that made sure the story stayed interesting or moved along. Now, in the second novel, an image begins to form as to why the first novel was the way it was. What these novels tell are actually two stories - the story of Charlie Tuesday and his background (lost in the past), as well as the story of a historical (let's still call it that, even if - well, disclaimer mentioned above) event or episode. That is not uncommon. What is, however, unfortunate, is that these two stories vie for attention, fight for the spotlight, and drag one another down. They clash and clang into each other, and they just do not gel. In the long run none of those really gets the attention it deserves. And that is a pity, because it makes these stories just...
...well, just not work. What we have is a story about a protagonist that the author strongarmed into consecutive interesting historical events, so that the framework is not "just another tale of Stuard times", but "wow, a tale set at one of the most harrowing events in London history".
Not to mention the change that the antagonist undergoes, including basically retconning his personality traits emergent in the first novel, to better fit the character needed in this one. To be honest, I am glad this is over and done with (at least I hope so). Because, as audio-book fast food goes, these books are okay, but if I hear one more Frankensteined Blackstone version, I'm gonna give up on the rest of them.