"In the dazzling conclusion to the Greystone Secrets series from New York Times bestselling author Margaret Peterson Haddix, the Greystones and their doubles, the Gustanos, must team up to save the alternate world--before both worlds are lost. All secrets are revealed in this page-turning, suspenseful story that shows the importance of teamwork, telling your story, and taking action when it matters most."--

From her home in Lidice, Czechoslovakia, in 1942, eleven-year-old Milada is taken with other blond, blue-eyed children to a school in Poland to be trained as "proper Germans" for adoption by German families, but all the while she remembers her true name and history.

When suicide becomes a worldwide epidemic, the only known cure is The Program, a treatment in which painful memories are erased, a fate worse than death to seventeen-year-old Sloane who knows that The Program will steal memories of her dead brother and boyfriend.

Members of an elite squadron of mutants, the telepathic twins, Ellie and Mika have specialized skills that will enable them to steal the top-secret formula for an age-reversing drug developed by rebel scientists on the wild side of The Wall. Juiced by these potent pills, the cadaver-like Gorman foresees a future in which he'll be forever young - released from the machinery that now supports him. Unless the twins have a master plan of their own: to...