Throughout the hunt for the 39 Clues, Amy and Dan have encountered some of the darkest aspects of history... and had to deal with the role their family played. But are they ready for the truth? In this thrilling ninth installment, Amy and Dan hit the high seas as they follow the trail of some infamous ancestors to track down a long lost treasure. However, the real prize isn't hidden in a chest. It's the discovery of the Madrigals' most dangerous secret...

A disgruntled big sister reveals unpleasant facts about babies.

When eleven-year-old Gregor and his two-year-old sister are pulled into a strange underground world, they trigger an epic battle involving men, bats, rats, cockroaches, and spiders while on a quest foretold by ancient prophecy.

The exiled Princess Shiori must unravel the curse that turned her six brothers into cranes, and she is assisted by her spurned betrothed, a capricious dragon, and a paper bird brought to life by her own magic.

With goblins, trolls, and the house boggart all trying to get them, the Grace children turn to Great Aunt Lucinda for help.

Lord Cassia is taken prisoner, while a plague sweeps over the land. Three years later, he wants only to return to his home. Meanwhile, his home has changed, and an assassin has targeted the queen.

Third-grader Clementine tries to adjust to the news that her perfect family of four is adding a new brother or sister.

Separated when the Fangs of Drang invade Ban Rona, the three Igiby siblings face sea dragons, Stranders, Ridgerunners, Cloven, and more in their final, epic battle.

Ginny is unhappy when her family moves from Chicago to upstate Michigan for the summer; her father has a job restoring a 1930s mansion, but there are rumors about Woodmoor and the forest next to it: rumors about strange mutant creatures; Ginny, an aspiring mystery writer, is soon half convinced that the rumors are true, because something or someone is haunting the house--and she plans to investigate, with the help of Will, the older boy who lives...

Amy and Dan are shocked to learn that Outcast, a violent renegade who is threatening the lives of innocent people, may be a Cahill family member who is determined to exact revenge.