I think the first half of this book was incredibly immersive, your tried and true children's adventure where our hero is waylaid by nefarious adults who want something from him and comes across several characters across his journey. But as the book got to the middle it started to drag a little bit for me, it didn't really keep up the momentum. Cora and Jack felt so flat as characters that I never really was that interested in them. 

The end feels a bit too slapped on, a bit too much of a redirected course that it doesn't feel natural, or, at least, it didn't get the build up or pay off to feel natural.