Thirteen-year-old Megan Montgomery's world is falling apart. Her father's promotion means leaving her whole life in New York behind. She finds herself transplanted to a huge house in the English countryside, with no one for company but the distant staff. Her new school only adds to her misery—neither the girls nor the teachers seem to like her. Then Megan meets three girls who actually talk to her instead of about her, and at first she thinks things are getting better. The girls seem more interested in the strange rumors that the house is haunted. Megan invites them to sleep over for the weekend. A discovery of a cryptic poem, a key and a diary written by the builder of the manor—an eccentric archaeologist turns the sleepover into a treasure hunt. Clues lead the girls to believe the Parthenon holds a great secret and suddenly they find themselves sucked into one man's version of Ancient Greece. The only way home is to find an object thought to be mere legend. If they survive that long.

Just when everything was under control... Megan has embraced her role as the Librarian, protector of the Library of Athena. She’s spent her entire summer teaching herself magic (al though it doesn’t always work out the way she wants) and studying the Library’s secrets. The Order of Ares, an organization bent on stealing all of the Library’s artifacts, are always at the back of her mind, though they’ve been quiet for awhile. Then she is forced into yet another enchanted story. Or rather, the story comes to her, somehow ripped from the pages of the book and brought to life. She and her friends must fight their way through an imaginary Ireland, where danger lies around every turn, and find the mythical Sword of Danu. It’s a race against time—because the magic is spreading. The manor is being overrun, and Megan, Rachel, Claire and Harriet must fight through what was supposed to be an imaginary world to find the sword and return things to normal.