I picked this up at a booksale and didn't realize it was part of a series until I started reading it, so if my criticism of something was explained in a later or previous book that's why.
I was really intrigued and excited when I first started reading it! Dulcie seemed like a fun character, I was interested in learning more about Mr. Grey and uncovering the mystery. The further I got in the book the less excited I was though, there isn't any particular reason for this, I just felt like the story kind of hit a lull close to the final act, maybe it was just me. I also started to like Dulcie's character a little less, she just really didn't seem to listen to anyone, or take any of their advice. I get that characters need flaws, and if they don't have them it's not good writing, it just got on my nerves a little bit.
The book felt overcrowded to me, you have the main mystery of what happened to Amy, and the Email system, then there's the "is Chris a werewolf or is he cheating?" mystery, then there's everything going on with Gus and Mr. Grey, and then there's the mystery of who wrote the book Dulcie is writing about. Maybe they're all plot threads from the previous books, but it just felt like too much was happening at once. Also when we're introduced to Dulcie's friends in this book there's one couple who barely get a line, and they don't really have much to do with the story other than knowing Amy. They probably had more to do in other books, but it just felt strange.
There were some things I really liked, I thoroughly enjoyed all the scenes with the cats, and most of the characters were fun to read about. I probably would have enjoyed this book more if I had read the previous ones, but that's my own fault. Overall it was fine, I wasn't insulted by anything, and the writing for the most part was entertaining.