Confessions of an Ugly Stepsister and Wicked being two of my favorite books, I was excited to dig in to Mirror Mirror. However, after only about two dozen pages I found myself losing interest because I was profoundly confused about who was telling the story.
In a nutshell, that was the main problem I had with Mirror Mirror: though Maguire's descriptions were as textured as ever, the fragmented narration made it difficult to fully relate to the characters. The characterization in his other books was so layered that I cared about the major and minor characters alike (even in Son of a Witch, which while good was not quite as dazzling as its predecessor). This story focuses on Bianca and her father, Vicente, but I did not feel particularly connected to either of them - they seemed to function more as symbolic placeholders than as actual people. The one real exception to this problem was Lucrezia Borgia: Mirror Mirror was really her tale, and she was by far the most engaging character to me. But her voice is only peppered throughout the narrative; Bianca, Vicente, and the dwarves also speak at different times, and I found the structure too fragile to be effective.
The magical elements in this story did not gel for me, either. The magical elements in Wicked were inherent to the story and Confessions used folk superstition to create an air of the supernatural, but I did not feel I had to totally suspend disbelief to read either one. With Mirror Mirror, though, the branch from the Tree of Knowledge was a hard pill to swallow (what the heck was up with the final chapter?), as was the dwarves' characterization. The dwarves are first described as primitive creatures born of the earth, more mineral than human, yet simply by Bianca speaking to them are they able to speak the languages of men with complete fluency. While I realized that Maguire was asking the reader to explore the idea of imagining something into your own reality, that whole concept seemed out of place in this setting.
I managed to finish this book because I do adore Maguire's descriptive prowess and the sly wit he incorporates into the dialogue, but Mirror Mirror is definitely not his best showing - which is sad, because he had some fantastic ideas to work with. If you're a fist-time Maguire reader, start with Wicked or Confessions of an Ugly Stepsister.