It's 1581 and Barnabas and Temperance make their way to London in search of Temperance's lost love. But quickly, they call into a sinister world of poltergeists, spies, lynch mobs, and even a plot to kill Queen Elizabeth I. Above all else, they meet Doctor John Dee, who remains one of the most intriguing characters from Tudor times - a strange mixture of serious scientist and dabbler in the paranormal. As Maggie Pearson says, 'Nobody in Elizabethan England knew the difference between astronomy and astrology or chemistry and alchemy. Or even between mathematics and magic.' His sole quest seems to have been trying to understand how the world worked, but he soon got side-tracked into magic ...