In her alternate England of 1851, fifteen-year-old Sophronia tries to uncover who is behind a plot to control a prototype that has the potential to alter human and supernatural travel, and to learn what role Mademoiselle Geraldine's academy for young spies plays in the affair.

Talking paintings and animals help Kay in his attempt to outwit the witches and locate his great-grandfather's buried treasure.

In World War II England, orphaned siblings William, Edmund, and Anna are evacuated from London to live in the countryside, where they bounce from home to home in search of someone willing to adopt them permanently.--

In 1940 England, stuck in a train tunnel while German fighter jets fly overhead, Barney hears an unlikely story of a highly decorated World War I soldier who once had a chance to kill young Adolf Hitler.

Fourteen-year-old Johnny Trott, a bell-boy at London's Savoy Hotel in 1912, becomes caregiver to Kaspar Kandinsky, the Prince of Cats, and soon the two are stowing away on the Titanic, where they are befriended by the Stanton family of New York.

Thirteen-year-olds Bertie Bradshaw of London and American Eleanor Shea team up to decipher a coded notebook and stop a double agent from revealing secrets about the upcoming D-Day invasion. n World War II London, a young spy named Bertie, his strong-willed American friend Eleanor, a Jewish refugee named David, and a dog called Little Roo try to prevent a double agent from giving secrets to the Nazis.