H.A.L.F. 9 has taken his first breath of desert air and his first steps in the human world. Created to be a weapon, he proved too powerful for his makers and has lived a sedated life hidden from humans. But he has escaped his underground lab he called home, and the sedation has worn off. He has never been more alive.

More powerful. Or more deadly. Erika Holt longs to ride her motorcycle east until pavement gives way to shore. She bides her time until graduation when she'll escape the trailer she shares with her alcoholic mother and memories of her dead father. But a typical night in the desert with friends has thrust Erika into a situation more dangerous than she ever imagined. Circumstances push the two together, and each must make a fateful choice. Will Erika assist H.A.

L.F. 9 in his escape despite her "don't get involved" rule? And will H.A.L.F. 9 let Erika live despite the fact he was trained to kill? The two may need to forget their rules and training and if either is to survive the dangers of the deep beneath them.