Oh god oh god this book!! Wow. Within the first chapter, I already knew I was going to love it. Lily, a girl who (in our world) is extremely sick and allergic to everything, has a seizure at a party one Friday night. She ends up being transported to a very different world that is also located in Salem, Mass. The alternate universe piece was REALLY freaking cool. Lily's other self, Lillian, is an evil witch who has been killing her own people for some unknown reason that is supposed to help their world. The world-building in this book was just amazing. Realistically, this book was definitely an introduction to the rest of the series in terms of setting up this alternate universe. The reader slowly learned about witches, crucibles, the Woven, the Outlanders... it was so detailed and complex! Because of all of this world-building and setting the stage for the next books in the series, there was a little less action than I expected. They spent a lot of time laying low and figuring out what to do next while Lily uncovered her abilities. It was interesting, don't get me wrong, but I just felt like not much actually happened in the way of plot. The ROMANCE though... talk about slow burn! God I can't wait to see where it heads. It was so nice to see characters not rush into everything for once, even though there was some kind of early (definitely not instant) attraction between them. The story itself has me completely enthralled and I can't believe how long I probably have to wait for the second book! As far as characters go, Lily is stubborn and sarcastic, but still extremely likable. She's loyal, even to people she's only known for a brief period of time. I can't think of any times where she really annoyed me, which is surprising; I tend to find something about every MC kind of irritating. There was one moment where I kind of scratched my head about her decision, at the end of the book, but I think it comes down to loyalty and her want to make the world a better place..regardless of which world she's living in. Lillian completely fascinated me. I'm DYING to know what's actually going on in this crazy bitch's head. She has all of these ideas and plans that somehow involve making her world better, but doing a lot of evil things to achieve that goal. Something must have happened to her that made her snap. I can't wait for the rest of the series to give me that info! I loved Rowan; that's all I'll say on that. 
 I was instantly attracted to the writing style. I loved that the book, while dealing with somewhat serious topics, still managed to make me laugh out loud sometimes. I'm not sure if this was more the actual writing or the character of Lily; either way I was hooked from the start. As I said before, the flow of the book was a bit slow at times, but I still really enjoyed it. The world-building happened gradually and kept me intrigued. 
 If you're a fan of books about witches and/or alternate universes - definitely read this one. People who are fans of fantasy books that have complex world-building should also pick this up immediately. The main part of the book that was interesting to me was learning about Salem and all of the powers/abilities people have. The entire book was focused on building up this new place, so be prepared for a little less action and a little more cool descriptions. I haven't read her other books and I'm not sure how they stack up, so I'm unfortunately not sure if previous Angelini readers would like this one! All I know is that I definitely plan on reading more of her books. 
 Overall, this story was extremely interesting and helped transport me into a completely different world. I do wish there was a little more action throughout, but at the same time I'm satisfied with the amount of time and effort the author made for world-building. I also wish there was more actual world-walking... I mean, that IS the title of the series. Lily was in this "other Salem" and I kept waiting for her to go back to her other world. That's a pretty complex process though and I don't want to give too much away. One tiny thing that bugged me was the excessive use of people's names. You know, like in Titanic when Jack and Rose are constantly saying and yelling each others names as if it's the only world in their vocabulary? That kind of happened in some unnecessary spots, in my opinion; I'm not sure why that's something that bugs me but whatever. THE ENDING made me want to scream and find Josephine Angelini to hover over her shoulder and force her to finish/publish/give me the second book right away. Talk about a cliffhanger. (I mean, not exactly like "holy crap I can't believe that happened," but more like "holy crap I need to know what happens next.") What the FUCK is going to happen next????????