The man who enters Geiger's house is Eddie Mars. Marlowe tries to talk himself out of the situation, saying that he and Carmen are business acquaintances who stopped by Geiger's to pick up a book. Mars does not believe Marlowe. He allows Carmen to leave, but tells Marlowe he would like to talk to him a little bit longer. Mars then adds that he has two of his men outside, who would be willing to do whatever he asks them to do with Marlowe. Carmen runs for the door and leaves.
Eddie Mars claims that he senses something is wrong, and he then notices a spot of Geiger's blood on the floor. Marlowe acts as if it is the first time he has seen the blood. When Mars threatens to bring in the law, and Marlowe does not react, Mars asks Marlowe to explain who he is. Marlowe tells him his name and says that he is a sleuth. Marlowe then continues by saying that Carmen is a client whom Geiger had involved in blackmail—they had come to the house in an attempt to solve the problem. The door had been open. When Marlowe asks how Mars got a key to Geiger's house, Mars says that he owns the house Geiger lives in, and that Geiger is therefore his tenant.
Geiger and Marlowe embark on what is one of the many quick, "hard-boiled" conversations in the novel. Mars acts as if he simply wants to know what has happened to Geiger, as Geiger has been missing from the store and nobody knows where he is. Marlowe tells Mars that he knows who Mars is, and that he knows Mars probably provides the kind of "protection" that someone like Geiger needs in the pornography business. Marlowe also adds that someone is trying to move in on the business because he thinks Geiger is dead. Marlowe continuously plays on Mars, revealing only what he wants, when he wants, in order to gauge Mars's reactions.
Eventually, Marlowe annoys Mars, prompting Mars to call for his "boys," his gunmen, with a whistle. The two gunmen enter and, upon Mars's request, they frisk Marlowe for weapons. They find that he is unarmed, that his name is in fact Marlowe, and that he also does in fact have a detective license. In the end, Marlowe does not give any of the information he holds about Joe Brody, Carmen, or anything else. Eventually, Mars lets Marlowe go. Marlowe goes back to Hollywood.
Marlowe goes back to Joe Brody's apartment building. He knocks on the door. Marlowe eventually makes his way inside by telling Brody that he knows Brody has Geiger's books. Marlowe says that he has the list of customers and that Brody should, therefore, talk. Brody has a gun, and points it at Marlowe. Agnes Lozelle, the blond from Geiger's shop, is also in the room. Agnes initially denies Marlowe's accusations about the kind of "smut" business Geiger was running out of the bookshop.
Marlowe explains, however, that it may seem to others that Brody had every reason to have committed the murder—even if he did not—in order to take over the porn racket that Geiger owned and that Brody now has in his possession. Marlowe also says that he knows Brody has the pictures, that he sent the blackmail letter to Vivian, and that Agnes was the female voice that delivered the telephone message to Vivian. Brody, as he starts to give in to Marlowe's pressure, relinquishes another clue. He asks if the "witness" Marlowe mentions regarding Geiger's murder was the "punk kid" that worked at the store who disappeared after the truck left. This young man is a new character whom we later learn to be Carol Lundgren, Geiger's homosexual lover.