Between 4 and 5 stars here 
 The book starts with a letter written by Myfanwy (pronounced Miff-un-ee) Thomas to the person who is now inhabiting her body after her memories have been stripped away. This person is standing in the rain surrounded by a ring of dead, gloved people. Myfanwy gives her instructions on how to stay safe and a choice - try to escape and build a new life, or take over Myfanwy's life and figure out who did this to her. 
 You would think the choice would be obvious, but it isn't, not when you find out you have superpowers and have an unknown menace after you. 
 And then the story is off and running, through the halls of the Checquy, a secret British organization that uses people with powers to protect the normals from things that go bump in the night, blobs that consume everything and everyone, and other threats that are better left in the shadows. 
 Throughout it all, as the new Myfanwy comes into her own, we also get a good sense of the old Myfanwy through her letters and notes. I've seen the letter effect done well and not so well, but here it flowed so well with the story that I looked forward to reading about old Myfanwy, her thoughts, fears, and observations. 
 There is no romance in this book. Old Myfanwy was adverse to any kind of connection to others, so it was a good juxtaposition to see that the first thing new Myfanwy does is start forming relationships. There is the friendship with long-time secretary Ingrid, the new team with American Shantay, and a new chance at family with Bronwyn. I liked that there is no romance here. In a lot of the books I usually read, the heroine would team up with a hero and there would be the simmering sexual tension. It was refreshing to not have that dynamic. It also worked best, I think, with the pace of events. 
 I don't know if there will be further adventures of Myfanwy Thomas, but I hope that O'Malley has another book out soon. I'll be reading it.