The story of Oliver Twist is a dark tale of corruption, degrading living conditions, and the terror of unanticipated violence. The novel takes place against a background that is by degrees appropriately sinister. Slime and filth seem inescapable. Even the elements conspire to accentuate the dismal atmosphere; the weather is often bitterly cold, and rain and fog are frequent.
Because criminals are thought to be creatures of the night, a large amount of significant action that takes place after dark. Sunlight rarely penetrates their gloomy world and even then perhaps only to mock — as on the morning that Nancy is killed. The only period of sustained brightness is during the summer months when Oliver stays with the Maylies at their rural cottage. Even then, black shadows are cast by Rose's near-fatal illness and the chilling intrusion of Monks and Fagin.
The novel deals mainly with poverty and crime — the results of abandoning the rules and practices of social awareness and compassion. The criminal elements in the novel represent the outcasts of society who lurk inside crumbling ruins. These structures represent the tottering institutions that have helped to deform their lives. In Dickens's descriptions, the words "neglect" and "decay" recur insistently. And it has been the neglect of human values that has fostered the spiritual decay that is so aptly reflected in the odious surroundings.