In this young adult urban fantasy, war is coming to London. The destructive Reach is killing the city and his opponent the Lady of the Streets is missing. Only her son, sixteen-year-old Filius Viae is left to recruit her supporters and defeat Reach. But he is young, and frightened, and not a general. This battle is going on concurrently with our contemporary London but completely overlooked by almost all of the normal human inhabitants of the city.Beth Bradley is one of the exceptions. She is a sixteen-year-old artist who uses London as her palette. She and her friend Pen spend many nights with Beth tagging the city and Pen leaving bits of poetry by the art. Beth is escaping a home filled with grief and a severely depressed father. After her mother's sudden death, her father gave up on life and on Beth and spends all his time sitting a chair and reading the last book his wife was reading over and over again. Beth works our her grief by being angry and by leaving her paintings all over town. Pen is her only friend but, when Pen seems to betray her, she is cut adrift and decides to run away.She meets Filius and is soon swept up in the up-coming war and in a world she couldn't have imagined. Tom Pollock's imagination has filled London with a wide variety of unique creatures from girls made of electricity to ghost trains to a guardian who reconstructs itself each day from the garbage and worms, roaches, and maggots in the trash. And that doesn't even include the Pavement Priests or the Mirrorstocracy or the Chemical Synod whose equations always balance. All of those characters are loosely aligned on the side of the Lady of the Streets, the Goddess Mother Viae. Reach's side include the Cranes and the scaffwolves and the Wire Mistress who is Reach's right hand who steels humans to use as hosts.When Beth goes missing, it is up to Pen and Beth's father to try to find her. Along the way Pen is captured by the Wire Mistress and Beth's father joins in with the Pavement Priests. There are many battles and characters we have come to know don't always survive. But those who do survive are stronger and better people. This is a gritty and sometimes frightening story that will touch the heart and the imagination of the reader. I recommend it to older fantasy lovers. It was a dense read with a lot of time spent introducing the many characters and the conflict but will repay the reader who stays with the story with many memorable characters and much to think about.