The chapter opens with Sikes sitting with his dog in his filthy, dilapidated apartment building. Sikes mistreats his dog, beating him and yelling at him, and though the dog fights back he remains loyal, for now, to his master. Fagin enters the apartment and interrupts the battle between Sikes and his dog. He hands over an amount of gold he has owed Sikes (Sikes appears to get a cut of some of the robberies orchestrated by Fagin and his boys).
This scene elaborates on the nature of the business relationship between Sikes and Fagin. It seems that Fagin "contracts" Sikes to do particularly dangerous or "dirty" work for him. Fagin, as is again insinuated here, is far too cowardly actually to put himself in danger; he merely coordinates crimes.
Another Jewish man appears, this one named Barney: he speaks throughout the novel as though he has a serious head-cold. Barney tells Fagin that Nancy is nearby, and Fagin and Sikes ask to speak with Nancy; they tell Nancy, once again, to be "on the scent" for Oliver, and Sikes and Nancy walk out together—it appears that he and Nancy have some kind of romantic relationship.
Barney is the comedic foil to Fagin—also Jewish, but incapable of organizing much of anything, and not especially bright. Barney's cold, which causes him to pronounce words with extra Ds, is used heavily by Dickens for humorous effect.
Oliver, meanwhile, has been walking to the book-stall with Brownlow's books. As he nears the stall, he is intercepted by Nancy (Sikes has gone his own way) who throws an arm around him, trapping him, and proclaiming aloud that she has found her long lost brother. Sikes emerges, with his dog, from a nearby beer-shop, and proclaims, too, that Nancy has found her brother; shopkeepers in the area chastise Oliver for running away from his family.
Another instance of Oliver's terrible luck early in the novel. Of all the places Nancy and Sikes could have been, they chose to look at the book-stall the exact moment Oliver is there (Oliver has only been to this stall twice in his life, and both times some terrible fate befalls him). Nancy demonstrates, once again, her skill in play-acting, by pretending to be Oliver's sister.
Oliver cannot counteract the combined force of Nancy and Sikes, who begin dragging him back to Fagin's apartment. Meanwhile, Grimwig and Brownlow continue sitting in the parlor, wondering if Oliver will return.
A scene of great sadness. All Oliver wishes is to return to his new "family," in Mr. Brownlow, but he is prevented by another stroke of terrible luck.