When cyborg dragons threaten Drakopolis, dragon racer Abel must find a way to save both it and them.As in the series opener, it's cops vs. criminal gangs both in the sprawling, corrupt city and in 13-year-old Abel's family, where his older brother, Silas, works for the Dragon's Eye secret police and his big sister, Lina, is a fugitive member of the politically subversive Sky Knights kin. He himself only wants to train and race dragons-particularly after meeting Brazza, an illegal mixed-breed flyer of touchy disposition and astonishing intelligence. While the plot does indeed feature two breathtaking, high-speed aerial races among the skyscrapers and a massive climactic melee featuring hundreds of maddened dragons with cybernetic enhancements and hacked DNA, it's more than just a pretext for set piece battles, as London also perceptively explores both the dynamics of a close family beset with conflicting loyalties and issues tied to subjugating and experimenting on wild creatures who don't talk but can, it turns out, sing and who, in Abel's view at least, are deserving of freedom. Lighter touches, such as 8-ton Brazza's fondness for being read to and occasional mentions of an anarchistic kin dubbed the Wind Breakers, leaven the proceedings. The human cast, though it presents largely White, does include one nonbinary supporting character, a boy who has a dragon queen act, and glancing mention of same-sex crushes.Breathless action, lots of dragons, and chewy themes to boot. (Fantasy. 9-13)