In the depths of the underground city of Grimhold, twenty-one-year-old Arabella yearns for the open spaces in the world above, even though the toxic air and the winged enemies in the sky are a threat to her life. Stay hidden. Stay quiet. And survival will be easy. Until Shaw, a Skylark, finds her. However, Shaw doesn’t fit the rumors she has grown up hearing. He’s kind, and caring, and seems to want to end the divide between their two kinds as much as she does. And most importantly, he has not tried to kill her. That is because of the secret tied to Arabella’s very essence. Arabella’s rare ability to clean the toxic air with her lungs. His little secret Vy. As their connection deepens, so does the danger. The toxic air is rising to the skies and causing newLark’s wings to grow inward, killing them. Arabella is the Skylark’s ultimate prize in their deadly hunt for survival. Arabella must evade being captured and experimented on by the Skylarks by trusting a secretive one that could cost her city, her heart, and her life.