Text and detailed drawings follow the planning and construction of a "typical" castle and adjoining town in thirteenth-century Wales.

Now thirteen, Meggie "reads" herself into Inkworld, where she, her family, and the characters in the book face chaos and danger as the original creator of the world frantically tries to redirect the story.

As Bluejay--Mo's fictitious double--tries to keep the Book of Immortality from unraveling, Adderhead kidnaps all the children in the kingdom, asking for Bluejay's surrender or the children will be doomed to slavery in the silver mines.