There's a lot to love about this book. From its heady themes to redactions and inserted reports, it's hard not to get sucked into the Antimemetics Division alongside the characters. The Unknowns are intriguing, unique, and often difficult to grok. The complexity of the Unknowns, the memory manipulation, and the physicality of U-3125 are my kind of science fiction. The reason this read didn't rank higher is because the last quarter of the book is messy and in many ways anticlimactic compared to everything that came before. I was hoping for a crazy, mind-bending finale and got something much less interesting.