S.L. Huang’s ROOT OF UNITY is the latest in the Cas Russell series ( Russell’s Attic Series) and it is nearly a nonstop adrenaline bang-up car-wreck of an amazing ride. The TL;DR is BUY THIS BOOK AND THE REST AND READ THEM IN A SINGLE GO.

Fresh from her adventures in Book 2 ( HALF LIFE)  Cas finds her morality-map fraying at the edges, and her usual coping methods are collapsing around her, at the worst possible time. The third book in the series sees her lethal brand of math-fu joining forces with a hacker named Checker, and a former private investigator named Arthur to find a kidnapping victim, and apparently the answer to a math problem that would change the world forever.

The stakes are higher for everyone this time, with Cas’s calculus martial arts ratcheting up even as she personally begins to fall apart. Expect no easy answers, and the slow simmering build-up to the Twist is presented excellently. Huang’s prose disappears behind the story, which is by turns hilarious (“He’s fine. He had a building fall on him.”) tragic and always action-packed. As someone who HATES math (I have dyscalculia) I love how the story presents mathematical ideas in a way that a total non-numbers type can follow, and the plot never slows down for it. 

Cassandra Russell is an excellent heroine, a woman of color who is bad ass, not beautiful, competent, not cute, and would likely hold her own against James Bond and Indiana Jones. Huang’s a rising talent in the sci-fi world, and I would not be surprised to see her books optioned in Hollywood soon. 

S.L. Huang’s book is tightly written, and is a perfect example of a compelling page-turner. I read it in two sittings, in the middle of the night and as soon as I woke up the next morning. 6 out of five stars.