As her mother prepares to be a contestant on the 1980s television game show, "The $20,000 Pyramid," a twelve-year-old New York City girl tries to make sense of a series of mysterious notes received from an anonymous source that seems to defy the laws of time and space.

Presents the continuing adventures of Henry York, who has been living in Kansas with his cousins, where he discovers doorways leading to other worlds and becomes involved in a multi-world struggle between good and evil.

Meg Murry and her friends become involved with unearthly strangers and a search for Meg's father, who has disappeared while engaged in secret work for the government.

On a vacation with their mother and stepfather, Jane, Mark, Katharine, and Martha find themselves overwhelmed with a lakeful of magical adventures after Mark captures an ancient turtle that seems to have extraordinary powers.

In book 2 of this trilogy, Abby and Derick begin their second semester at Cragbridge Hall, the most prestigious secondary school in the world. But when Grandpa Cragbridge admits them to the Council of Keys--a secret group of people who have keys to travel back in time--strange things begin to happen. One by one, members are found unconscious and unable to wake, their keys stolen. Now Abby and Derick must scramble to figure out who is behind the attacks...

When her best friend, Libby, misuses instant transportation technology to alter her appearance, seventeeen-year-old Clair is drawn into a shadowy world of conspiracies and cover-ups as she attempts to save Libby from the hidden consequences of her actions.

After thirteen-year-old Tucker Feye's parents disappear, he suspects that the strange disks of shimmering air that he keeps seeing are somehow involved, and when he steps inside of one he is whisked on a time-twisting journey trailed by a shadowy sect of priests and haunted by ghostlike figures.

As a seventeen-year-old sophomore at NYU, Casey wears different disguises to fit in, but when she starts hearing voices and seeing visions, she travels to a remote beach town and searches for answers.

Marguerite Caine's physicist parents are known for their groundbreaking achievements. Their most astonishing invention, called the Firebird, allows users to jump into multiple universes-and promises to revolutionize science forever. But then Marguerite's father is murdered, and the killer-her parent's handsome, enigmatic assistant Paul- escapes into another dimension before the law can touch him. Marguerite refuses to let the man who destroyed her...

Derick and Abby Cragbridge continue their seventh-grade year at Cragbridge Hall, where they run into competitions, new friends, virtual zombies, and real danger.