After a year at the Stellar Academy and a devastating trip to the soothsaying Sibyls in the mind-swirling Nebula, thirteen-year-old Orion Kim is confident he now knows who he is-or does he? When his return to the three worlds in the stars leads to violent emotional outbursts that leave him confused and unable to trust his own mind or body, Orion turns for answers to the people who have always helped him. This time, though, his mentors dodge his requests, holding secrets close and treating Orion like he is an odd, mythological relic rather than a confused teenager in need of guidance. When even Orion's friends seem afraid of what he's becoming, it's a mysterious memory-filled Door that may be the only way for him to reclaim not just his life, but his soul, too.But the Door may hold secrets of its own...