In this tale of London and its underground river system, Hyacinth must try and rescue her mum from some magical creatures including Salt Petre ( mud )men postal workers, a giant pig wearing a bathing suit called Oaroboarus and a wicked neighbor called Lady rosalyn.
I have the feeling that this is the start of the series. It was okay but at times a little tedious...just get to the point already!! The end of the story was better than the beginning. It is a book for children around the age of 10 to 11. ( )