This is the weakest of the Patternist series thus far. It's tightly plotted but the characters are hastily sketched. Despite this I couldn't put it down. The premise is strong and the world is both depressing and believable. The book fits into the scifi genre with both its strengths (premise, world building, plotting) and its weakness (character development). If you like scifi already it's an enjoyable read. I just know Octavia Butler can do better.