The Big Sleep takes place in a big city in America during the 1930s—the period of the Great Depression when America was, as a whole, disillusioned and cynical about its prospects for the future. Chandler mentions money throughout the novel as an ideal, a goal for the seedy crime ring that lives within the novel. Many of the characters kill and bribe for money. The opening page of the novel claims that Marlowe is "dressed up" because he is about to enter a house that is worth millions. Money, in short, is something that is coveted, enjoyed, and respected. This makes perfect sense given that the economy of the 1930s in America was in serious turmoil. Also, many of the characters find themselves in troublesome situations, such as Agnes Lozelle and Harry Jones, therefore mirroring the desperation in which Americans found themselves throughout the period about which Chandler is writing.
Branching out of the cynicism of the Great Depression, Chandler chooses not only to represent a world of money-hungry people, but also chooses to make this world dark and corrupt. No one, not even the law, is exempt from corruption in this novel: newspapers lie and cops can be bought. This corruption is reflected in various ways throughout the novel. First, The Big Sleep is dark in that it is a novel in which rain pervades. It is also a novel in which richness is juxtaposed against the grime of deserted oilfields. The oilfields themselves—including the deserted one with empty pumps and rusted remains in which Carmen attempts to kill Marlowe and in which Rusty Regan is lying dead—are symbolic. These oilfields are what made General Sternwood his millions. It is important that the luxury of the house, which has come out of the oilfields, is beautiful and gaudy; yet the place where the money came from is "dirty." Moreover, these oilfields imply a degradation of morality and a corruption; we sense that Sternwood's business was not always "clean." The oilfields are only one way in which this corruption can be seen throughout the novel, other examples are abundant.