YA (more middle school and up) Steampunk adventure. I give it 4.5 stars. 
 Loved it. So much fun. Modo (abandoned near Notre Dame) has a disfigured face and hunchback, but also has the power to shapeshift. As a baby, Mr. Socrates buys him from a traveling freak show and raises him, training him to be a future agent for a secretive English society. He grows up and finds himself investigating missing orphans, scientific experimentation, and threats against the country from an evil organization. And he has cool gadgets and a partner in fellow orphan Octavia. I'm not going to go into the details - had too much fun reading it to want to spoil Modo's adventures. 
 I would say that there was one part at the end where I wished it had been handled differently, but then I remembered the age group that this is focused on and it makes sense. 
 Modo is superhuman in his abilities, but his caring of others (despite Mr. Socrates' efforts to isolate him), his longing to be accepted, to be able to show his face and find his own family makes him endearing and relatable. There are enough unanswered questions to populate many more books (such as who Mr Socrates is really, where Modo came from, etc). Looking forward to the next one.