Betteredge looks for Franklin in the library and sees Rosanna leaving the library. She explains that she was returning a ring Franklin had dropped upstairs. In the library, Franklin explains to Betteredge that he wants to telegram London requesting a "cleverer" investigator. He also reveals that Rosanna has acted strangely toward him and suspects that she might know something about the theft of the Moonstone. Betteredge searches for Rosanna, who has become ill and gone to her room. Penelope reminds Betteredge to be careful of Rosanna's feelings, as she is lovesick over Franklin.
Franklin and Seegrave ride to Frizinghall so that Seegrave can question the Indians and so that Franklin can send his telegram to London. The men return and report no success with the Indians, even with Murthwaite to translate.
With the introduction of the diamond into the Verinder household, a feeling of exoticness and danger emerges. The exoticness of the diamond and its background make the danger seem less real, as when Rachel is delighted to hear in England that her life would be in danger in India if she were there with the diamond. The diamond itself, as we saw in Chapter IX, gives off, exotically, a dark brightness ("It shone awfully out of the depths of its own brightness" in a sunless room). Betteredge's narrative encourages a mysterious understanding that the diamond has created an atmosphere of strangeness and danger in the household, manifested by his own uneasiness and the sinister quality of the dinner conversation.
Yet the exoticness and explicit danger of these chapters of the novel are not presented as emerging from the diamond alone. Murthwaite works as a catalyst between English and Indian culture to explain the danger inherent in the Moonstone's history. Murthwaite exists as a kind of English spy on Indian culture and territory. This status makes him seem somewhat sinister and certainly exotic.
Though the Moonstone inspires a sense of exoticness and danger, its symbolism also connects it to female sexuality—Rachel's sexuality specifically. The diamond is connected with female forces through the symbol of the (feminine) moon. The circumstances and consequences of the theft connect the stone to Rachel's sexuality. The theft is committed on the night of Rachel's eighteenth birthday, her coming-of-age. The strange dinner conversation on the night of the birthday—especially the conversation of Franklin Blake, who speaks of female infidelity and breeding bulls—is sexual in subtext. Finally, the diamond is stolen out of Rachel's bedroom during the night and produces an inexplicable change in her. Rachel seems moody and reticent, refusing to speak to everyone, most of all to Franklin Blake.
Once the crime is committed, the mystery plot splits into two threads. The remainder of the novel will concentrate both on finding the diamond's current whereabouts and also on reconstructing how, and by whom, the initial crime was committed. Superintendent Seegrave foolishly concentrates mainly on the first mystery, and it is not until Sergeant Cuff is called onto the case that much attention will be paid to reconstructing the initial crime. The rules of a mystery novel (in which things are often the opposite of what they seem to be) apply to the characteristics of the detectives themselves. Superintendent Seegrave is considered to be physically reassuring and have an air of confidence, yet his ineptitude will soon be revealed.