I was very impressed with the premise of this book, an American writer writing about the UK is quite unusual, and I am a fan of the Victorian era.
Character-wise, I thought that while the characters were better written than in the Mortal Instrument series, they still felt a little bit flat. It was interesting looking at how the characters resembled their descendants in New York, and which one of them carried the traits better. Personally, I found that Will’s incredible skill and self-confidence more annoying than Jace’s as he lacks the charm to go with it. Jem, on the other hand, is a much better companion and sidekick than Alec and Simon. I did think though that the role of Jessamine was interesting, as we have not seen anyone on the inside criticised the Nephilim in that way yet, although we do know that they exist. Tessa is a much better protagonist than Clary as she is less impulsive and is wiser.
I thought that the plot was well written and I liked the idea of the automatons (not just in this, I think that they are really cool) as a way to wriggle through the guards that the Shadowhunters had created. I did think that the twist at the end was surprising and was well thought out, however, I was certain that something of that type would happen to allow the story to continue.