This seems to be Thackeray as moralist. The preceding decade had seen an explosion in the new genre of crime novels which he believed had glorified criminals and raised lowlifes to hero status, culminating, at least in a literary sense, with the very recently published Oliver Twist. In this, his second novel after the highly amusing Yellowplush Papers, Thackeray set out to counteract what he saw as this pernicious trend.
His intention seems to have been to present banal lowlifes as exactly that. He succeeded so well that he created a very dull book about singularly unattractive and unappealing characters. ( )

Not a good book. Poor story, uninteresting characters, boring in all respects and the author constantly interrupts the story with silly comments of his own. Disappointing, coming from Thackeray, but I think it was his first novel. ( )