Kate, Michael, and Emma have passed from one orphanage to another in the ten years since their parents disappeared to protect them, but now they learn that they have special powers, a prophesied quest to find a magical book, and a fearsome enemy.

Jack and Annie, joined by Teddy and Kathleen (from earlier books), travel in the Magic Tree House to a land of snow where the Ice Wizard has captured Morgan and Merlin. The four friends must find the Ice Wizard's missing eye - or is it really his heart that is missing? Jack and Annie are joined by Teddy and Kathleen as they travel to the snowy Land-Behind-the-Clouds, where they search for the eye of the Ice Wizard and attempt to help Merlin and Morgan....

Beset by an enemy from within, Dan searches for the gypsies he once knew in York and is led inexplicably into a calamity involving the Black Death in a hostile country among frightened and superstitious people.

When twelve-year-old Becker Drane is recruited by The Seems, a parallel universe that runs everything in The World, he must fix a disastrous glitch in the Department of Sleep that threatens everyone's ability to ever fall asleep again.

Young Arthur Penhaligon must weigh an offer from Lady Friday that is either a cunning trap for the Rightful Heir or a golden opportunity that he must seize.

1916: The Western Front. Private Percy Blakeney wakes up. He is lying on fresh spring grass. He can hear birdsong, and the wind in the leaves in the trees. Where have the mud, blood, and blasted landscape of No Man's Land gone? For that matter, where has Percy gone?

2015: Madison, Wisconsin. Police officer Monica Jansson is exploring the burned-out home of a reclusive—some said mad, others alleged dangerous—scientist who seems to

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"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"--Provided by publisher.

Time-travelers Jonah and Katherine are summoned to help another missing child from history, this time Virginia Dare from the Roanoke Colony, but their journey is sabotaged and goes dangerously awry, leaving them in the wrong time period. Includes author's note about the history of Roanoke Colony and Virginia Dare.

"A playful and transcendent novel about language, family, and parallel universes"--

Seventh-grader Arthur Penhaligon returns to the parallel universe known as the House to fight his latest enemy, Grim Tuesday, whose greed threatens to destroy both the House and the Earth.