This book took be awhile to get through and I'm undecided on whether I should give it 3 or 4 stars. As of this moment I'm feeling it should be 3 (I reserve the right to change that answer however). 
 The book starts off with Diana in the library at Oxford university studying texts about alchemy when she runs across an old manuscript. We discover that this manuscript is magically protected, and we also discover that Diana is a witch. For some reason he magic breaks the spell on the book and she can open and read it. Being finished with it, she promptly returns it to the library to re-shelve. Little does she know that this single event sets off the rest of the events for the book. By being able to open the book Diana draws the attention of other creatures. By creatures we are talking yes, witches, vampires, and daemons. 
 When I first started hearing about this book I thought it would be more historical fiction about the witch trials or something. Then when I started to read reviews I learned that this is in the popular paranormal fantasy category. 
 For me, this book was slow going. It took me nearly two weeks to get through the book, but I believe that's just the nature of the book. It's a strange thing because I found myself really taking my time with the book, yet the book seemed to go by quickly. I guess it flowed really well from one circumstance to another. I did feel like it started to get predictable and started to follow a pattern by the end and that started to get old for me. There were some instances as well throughout where I wasn't surprised because I felt like it was just the natural progression for the book to take the direction it did. On the other hand, the few instances where I was surprised were wonderful. 
 The relationship between Matthew and Diana was sweet. I like books about "star-crossed" lovers who are told they can't be together because of society. Society here being the congregation of witches, vampires, and daemons who set up "laws" for the different species to follow in order to stay hidden from the humans. I liked the meeting of two different people and their discovery of affection for one another although in this case it felt very rushed. 
 Even though I, overall, like Matthew and Diana's relationship I started to get irritated with his need to protect her from everything. I liked when she would assert herself and inform him that she didn't need as much protecting as he thought, but then she would get into a bad situation and decide maybe she did want his over-protection instead of growing from it. 
 I also didn't care for the "cloud of doom" that seems to be hanging over everything. There were so many secrets that Matthew keeps from Diana. She knows this too and still allows him to keep the secrets. I liked Diana's unwaivering loyalty and belief in Matthew, and I hope that her positivity about him and the situation are correct. I really want everything to work out for them, but when you have multiple people telling you to "watch yourself" around the person you love it can be a little disconcerting. Deborah Harkness is probably testing our resolve on the situation as well. 
 Like I said previoulsy this book is slow going, but it kept my attention the whole time. It's a lot of introduction and some of the history and science that we are presented with can be a little overwhelming at first. I enjoyed the worls created. I especially liked when Matthew and Diana went to stay with Diana's aunts in her childhood home. I lked that the home was sentient and would add rooms on for visitors to stay in and unearth long lost items from the floor boards. Probably my favorite section. 
 The books ends on a slight cliffhanger. Nothing too overly dramatic. Sort of like a pause before lift off (if that makes sense). I hope that the next book in the trilogy we get to see Diana coming more into her powers and becomes a truly stronger woman who can stand beside Matthew if needed instead of behind him in some circumstances. She starts to make good progress towards the end of this book, and I hope it continues. Until Then!