Sure to inspire even deeper devotion among Lu's fans, this sequel picks up just three days after the Warcross finale, raising complicated questions about the consequences of technology and power. Emika Chen, exempt from Hideo Tanaka's unleashed algorithm thanks to a lucky accident, is reeling from Hideo's betrayal and the knowledge that Zero, the hacker whom Hideo hired her to neutralize, is Hideo's long-missing brother, Sasuke, whose disappearance drives Hideo to create Warcross and the algorithm. Having realized that the algorithm, meant to eliminate violence, may be causing people to commit suicide, Emika enters a tenuous partnership with Zero and the Blackcoats, a secret organization working to destroy the algorithm, and attempts to gain access to it by winning Hideo's trust. Though Emika maintains her moral center, she struggles to do right as the virtual world crosses into reality and becomes personal: "There's a point where the lines start to blur, and I am standing in that place now, struggling to see through the gray." Lu's futuristic world, with its immersive technology, feels dangerously within reach in this action-packed escapade with a thoughtful, emotion-driven core. Ages 12–up. (Sept.)

Gr 8 Up–Emika Chen has been betrayed by Hideo, the man she cared most about and tried to help. Blinded by his all-consuming need to find his long-lost brother, he now controls most of the world through an algorithm in the lenses that everyone uses to connect to the NeuroLink, the system by which they access the virtual world. Only a very few people, like Emika and her old teammates on the Phoenix Riders Warcross team, are still using beta lenses that allow them to circumvent the algorithm. This is encouraging crime bosses and criminals to turn themselves in, but others, maybe even innocent people, are committing suicide. Emika, convinced that she alone must stop the algorithm, agrees to work with mysterious hacker Zero and his Blackcoats to undermine Hideo. But there's a thin line between right and wrong, and she's not sure whom she can trust, other than her old teammates. Fans of Warcross will enjoy even more time spent in the game, along with intrigue, action, and mystery. Emika owns her flaws and still tries to do the right thing, even when she's unsure what that is. While the character development of some of her teammates feel a little flat, Emika, Hideo, and Zero shine through. VERDICT A necessary purchase for libraries that have Warcross; those where science fiction circulates well, should pick up both volumes in this duology.—Kelly Jo Lasher, Middle Township High School, Cape May Court House, NJ