Nobody knows that Nathan and his family are extraterrestrials, part of a select group taking part in an experiment meant to determine whether their people, the Kast, can live safely on Earth. Unlike his parents, brown-skinned Nathan was born in New York City and has never visited the Kast mothership (“the Wagon”). When he unexpectedly grows a sentient tail, though, Nathan is summoned to appear at the Wagon—a worrisome development, as several other Kast kids, including Nathan’s friend, Izzy, have been called there and have never returned. What Nathan learns on the Wagon (disguised as a storage facility) upends everything he’s ever known. Hester, the Kast leader, is thrilled with Nathan’s tail and instructs him and his family to return home. Before he does, though, Nathan stumbles upon Izzy, now an imprisoned laborer on the Wagon, who believes they’ve all been deceived: She and Nathan are not Kast, but human. It will be up to Nathan (and his tail) to rescue not only Izzy and the others, but the actual Kast themselves—who are not what Nathan has been led to believe—from Hester. Fast-paced and exciting, this sci-fi novel is full of surprises as it unfolds. It’s easy to root for Nathan, an affable protagonist who loves his friends and carries the weight of his family’s secret identity with fortitude.