"When her parents leave Willoughby Chase for a sea voyage, Bonnie and her cousin Sylvia are left in the cruel care of Miss Slighcarp. Together with Simon the Gooseboy, they make a daring escape, but they must find a way to wrest Willoughby Chase from Miss Slighcarp's evil clutches." --

On her way to England from Nantucket aboard a British man-o'-war, Dido has many adventures when the ship is diverted to the land of New Cumbria in the southern hemisphere.

Bound to keep a promise to her dead uncle, Is travels to the mysterious north country to find two missing boys, one of them a prince, and to discover why so many children in London are disappearing.

Simon, the foundling from the earlier book, The wolves of Willoughy Chase, arrives in London to meet an old friend and pursue the study of painting, but he finds himself in the middle of a wicked crew's plan to overthrow good King James and the Duke and Duchess of Battersea.

Although Dido Twite wants to return to England, she must first solve some mysteries in Nantucket.

The Wolves Chronicles continue as Dido and her friend Simon, Duke of Battersea, have many perilous adventures trying to protect the ailing King James from the plotting of the evil Baron Magnus who is determined that his brutish son Lothar will be the next king of England.