In their magic tree house, Jack and Annie are again transported to King Arthur's realm, where invisible beings, giant ravens, and mistaken magic spells have a duke's castle in an uproar on Halloween night.

"No visitors. No nights spent away from the apartment. No disturbing the other residents, all of whom are rich or famous or both. These are the only rules for Jules Larsen's new job as an apartment sitter at the Bartholomew, one of Manhattan's most high-profile and mysterious buildings. Recently heartbroken and just plain broke, Jules is taken in by the splendor of her surroundings and accepts the terms, ready to leave her past life behind. As she...

"The magic tree house takes Jack and Annie to Africa where they meet up with wonderful wild animals, a very hungry warrior, and where they even solve a riddle."--

The magic tree house transports Jack and Annie on a mission to the Ice Age where they encounter Cro-Magnons, cave bears, sabertooth tigers, and woolly mammoths.

"Josh and Amanda just moved into the oldest and weirdest house on the block. It might even be haunted. But their parents don't believe them. You'll get used to it, they say. Go out and make some new friends. So Josh and Amanda do. But these creepy new friends are not exactly what Mom and Dad had in mind.. Because they want to be friends ... forever..." -- P. [4] of cover.

"The decaying mansion is known as the old Willis place, even though no one named Willis has lived there for years.  Diana and her little brother, Georgie, know every inch of its extensive grounds.  They climb trees and swim in the pond.  And they can do whatever they want, even stay up all night.  They don't have to change their clothes, brush their hair, or go to school.  They have total freedom--as long as they don't leave the old Willis place. ...

Froggy and his friends build a treehouse, while avoiding help from his little sister, Frogilina.

Thirty-four-year-old Andie, hoping to cut the ties that still bind her to rich ex-hubby North, winds up instead getting drafted to "fix" the troubled orphaned children of North's cousin, who live with a grouchy housekeeper and a crew of ghosts that have an interest in the kids and their gothic mansion home. But there's no ordinary fix for this unruly bunch of living and undead as Andie tries to cajole them all--troubled and lonely kids Alice and Carter,...

"Their magic tree house takes Jack and Annie back to retrieve a lost story in ancient Greece, where they witness the original Olympic games and are surprised to find what girls of the time were not allowed to do" --Title verso page.

Follows three young operatives of a Psychic Detection Agency as they battle an epidemic of ghosts in London.