Anthony Horowitz 
Devil and His Boy [EPUB ebook] 

London is dirty, distant and dangerous … but that’s where orphan Tom Falconer is heading. And he’s got a whole assortment of vicious criminals hot on his heels. Tom is helpless and alone until he meets Moll Cutpurse, a thirteen-year-old pickpocket. Together they find themselves chased across the city by the murderous Ratsey. But it’s only on the first night of a new play — The Devil and his Boy — that Tom realizes that the fate of the Queen and indeed the entire country rests in his hands.