The Masquerades of Spring is the latest novella by Ben Aaronovitch. It takes place in the Rivers of London universe, but is set in Harlem, New York, in the 1920s. As with the longer RoL books it has a first person narrator, in this case Augustus "Gussie" Berrycloth-Young, a young Englishman living in New York. He was a contemporary of Thomas Nightingale at Casterbrook School, where young British gentlemen of the magical persuasion have been educated for generations, and was connected with the Folly (headquarters of the Society of the Wise) but is now a man of leisure, enjoying a life of jazz clubs, parties and gay hedonism.