The year is 1665.
A half decade after the coronation of Charles II, the unrest over the extravagance and corruption in his Court is growing. Then a cart filled with gunpowder explodes outside a government office. Thomas Chaloner is certain he will be asked to investigate but then is stunned when an incompetent is given that task and Chaloner is put on a case of the poisoning of birds in the King's aviary.