"When something crucial goes missing, eleven-year-old Olive and her friends must decide how to get it back--put their faith in a strange and dangerous magic, their odd new neighbors, or someone more uncertain and terrifying than both"--

With their mother still missing after going through a Civil War time portal in their spooky house, and their father in jail under a false accusation, Xander, David, and their younger sister continue to try to bring their mother back, now with the help of an old relative who has turned up unexpectedly.

An English girl, a Polish refugee, and a displaced boy from the Orient explore an island-strewn river flowing past the ancient manor house of Green Knowe.

"In the wake of a scandal, the Montrose family and their three daughters--Catherine, Lydia and Emeline--flee Boston for their new country home, Willow Hall. The estate seems sleepy and idyllic. But a subtle menace creeps into the atmosphere, remnants of a dark history that call to Lydia, and to the youngest, Emeline. All three daughters will be irrevocably changed by what follows, but none more than Lydia, who must draw on a power she never knew she...