Godolia enslaves and controls its populace using Windups, towering godlike "mecha" piloted by altered humans trained at the elite Academy. Sona is one of these pilots, implanted with wrist ports and an unmistakable glowing red eye that connect her to her Valkyrie. But Sona has a secret: she joined the Academy in hopes of destroying Godolia from within. Eris is the leader of a crew of teenage Gearbreakers, renegades from the Badlands trained to take down Windups from the inside. After Eris is captured and brought to the capital for questioning under torture, Sona rescues her and pleads to join her crew. What neither expects is their growing attraction. Human connections sustain this dark, action-packed debut, both in the tenderness between Sona and Eris and the familial bickering that animates Eris's crew in the midst of desperation, loss, and betrayal. The world building in this vaguely Asian, far-future dystopia leaves several questions unanswered, but its young author keeps the stakes high and uses popular tropes to great effect. The twist ending will propel its readers into the sequel.

Told in alternating perspectives, Mikuta-s fast-paced debut follows Sona Steelcrest, 17, who infiltrated the Windup Academy five years before the novel begins. Now, transformed into a cyborg Pilot of a mecha, Sona is determined to exact revenge against the system that destroyed her town. When she meets headstrong Eris Shindanai, -seventeen-ish,- a captive Gearbreaker whose mission in life is to destroy the mechas, the duo escapes Godolia and makes it back to the Hollows, the Gearbreaker Headquarters. Frantic, bordering on chaotic, fight scenes deftly convey the world-s reality, wherein second-guessing guarantees death. Sona and Eris are presumed South Korean through the use of familial words and references to Korean snacks, but the inclusion raises questions of geography and worldbuilding, since the past or present existence of Korea or other real-world nations is never determined or explained. Dialogue-based explanations feel slightly repetitive, and a last-minute reveal proves frustrating. Still, quippy exchanges among the inclusive cast bring a levity that balances their grim realities, and the cliffhanger ending of this action-packed series starter suggests that a deeper political conspiracy will unfold in the sequel. Ages 13-up. (June)