The Rule of Mirrors picks up where The Vault of Dreamers left off, with Rosie Sinclair having her consciousness fractured after failing to stop her nemesis, Dean Berg, from mining students' dreams. Rosie is still Rosie, but part of her is missing as well- and part of her consciousness finds itself in someone else's body. Althea is a girl in a coma after suffering an accident, and after receiving treatment where she is "seeded" with Rosie's dreams, she wakes up- but she's not Althea anymore. Now she's Rosie in Althea's body.
That's pretty much the set-up for this one. The story is told in alternating viewpoints- Rosie and Thea. Although they're both Rosie, in effect, and I enjoyed seeing the differences between them as Rosie's personality is fractured. The pacing of this one is just like the first book, and it was just as readable- I think I read it in two sittings.It's just an easy story to roll with. We find out more about the dream mining/ seeding process, which is kinda neat but also a little creepy, and we see a love triangle almost develop, with both Linus and Burnham as possible love interests for Rosie. This is actually one of the more interesting love triangles I've read in YA, and I'm normally not a fan of that trope, but Linus and Burnham are so different it makes it fun.
I've been a little suspicious of Linus, frankly, at times in this series and that continues here. Is he on the up and up? Hard to say. Rosie does a lot of traveling here, from Montana to Georgia and eventually back to the Forge school, where of course all the secrets are. Although we learn that there are other facilities, including one where Rosie is held prisoner for several months. The story is deepened although if I have one complaint, it would be that after three hundred pages we're still sort of where we were at the end of book one. Not a lot is resolved, and this is a trilogy after all, but like many trilogies I wonder if this one was entirely necessary?
Having said that I don't mind that much, because frankly this series is very fun. There are hints that not all is as it seems, and Berg seems to always be a step ahead of her, but Rosie is a plucky protagonist and I liked her- both versions of her. I think the author here plays with the concept of the personality fragmenting in an interesting manner- someone at one point refers to her as Rosie ego and Rosie id, and while it doesn't seem to be that simple, the principle may apply somewhat. This was one of the more interesting aspects of the story. Both versions of Rosie have different ways of dealing with the situation, and the story also raises questions about the nature of consciousness, and what someone might do if they could live in another body.
So even though I would have liked more resolution here, and this definitely feels like the middle book of a trilogy, I still recommend this heartily if you're a fan of the first book, or just want to read a fun series. The idea of mining and seeding dreams is a unique one, and the villains are nuanced enough that they are realistic (mostly), they're not just cardboard cut-outs, and I really like Rosie. She has her work cut out for her in the next one, and I'm looking forward to seeing where she takes the story. And oh yeah- Linus or Burnham. Or neither? I sort of have a preference, but I'm not telling.