Cricket Readers Recommend

This is an awesome book about a guy named Richard who goes into London Below ( The sewers of London) and goes on a strange juorney with a girl Door. She is trying to get to the angel Islington so she can find out who murdered her family, Richard just wants his life back. They are traveling with a Marquis and their body guard, Hunter. She is protecting them from the professional murderers, Mr Croup and Mr Vandemar who follow their every move.