In 1817 in England, two young cousins, Cecilia living in the country and Kate in London, write letters to keep each other informed of their exploits, which take a sinister turn when they find themselves confronted by evil wizards.
In 1828, English cousins Cecelia and Kate and their husbands search for a missing German railway engineer and with the help of their wizardry skills, uncover a plot that could endanger the unity of England.