Terry Pratchett's Dodger is a wry look at the London of Charles Dickens. Indeed, Dickens himself is a central character, as is the great chronicler of Victorian London, Henry Mayhew. Given how both these authors showed the dirty underbelly of the capital, it is no surprise that Pratchett's book too looks at life for the poorest of society.
Dodger himself spends his life underground, hunting the sewers for items of value that have been flushed down the drains and toilets of the world above. Its a life of poverty, violence and tragedy. Around this Pratchett weaves a wider story of how Dodger saves the life of a damsel in distress, while wooing the elite of Victorian London with his luck, charm and a lucky bit of rewriting of history by the newspapers. There's a great Jewish character, Solomon, who Dodger lives with, having saved him from a racist attack, who appears to know a radical named Karl (though one who hails from Russia, as opposed to Germany).
Dodger is a fun novel, it is not Pratchett's greatest, but it is aimed at young adults. Fans will enjoy it, though the younger ones will like the jokes about dirt and sewers far more than the older reader who will enjoy hunting out the Dickens references and Benjamin Disraeli exploring a sewer system with Joseph Bazalgette.