In A Companion to Crime Fiction published in 2010, Andrew Mangham asserts that “the 1860s was a decade that shifted criminality…from the slum districts of London to the comfortable firesides of nineteenth-century suburbia.” This trend was echoed in the sensation novels of popular authors such as Mary Elizabeth Braddon with Lady Audley’s Secret and Aurora Floyd, Mrs. Henry Wood and East Lynne, and Wilkie Collins with The Woman and White and The Moonstone. As the threat of crime moved from roadside to residential, a new kind of police force was needed in order to adapt to the investigational changes that came with examining private domestic spheres, rather than public spaces, in both the real and literary worlds. The Victorian age “was the first period to open its household doors to the scrutiny of professionals like police detectives,” writes Ronald R. Thomas, and this historic shift called for a modern officer who could carry out a thorough and discrete investigation using the most advanced and modern detection techniques, while still sensitively navigating the social and political boundaries which were a part of domestic order in the Victorian home.  Such an officer—the modern detective, really—would not only be difficult to find and to train but also to be accepted by the Victorian public, who already feared “that modernity itself was undermining domestic life.”
In July and September of 1850 Charles Dickens published a trio of informational articles in Household Words (HW) which both introduced the Victorian public to the newly formed, specialized subsection of the police force—the Detective Force—and addressed these exact anxieties about the intermingling of detection and domesticity. Created in direct response to the changing nature of Victorian crime, Dickens hailed the Detective Force as a “superior order of police…which consists of only forty-two individuals, whose duty it is to wear no uniform, and to perform the most difficult operations of their craft…to clear up family mysteries, the investigation of which demands the utmost delicacy and tact.” Dickens continued to write follow-up articles praising the superior crime-solving skills of the new Detective Force throughout the 1850’s and 60’s as editor of both Household Words and All the Year Round (ATYR). As both a staffer and author at HW and ATYR, Wilkie Collins was also fascinated by the development of the Detective Force, and kept in constant touch with Dickens about the details of current cases and the exploits of its most celebrated officer, Sergeant Jonathan “Jack” Whicher. Taking Dickens’ prior work from HW and ATYR, Collins moved the Detective Force from the real world into the literary through the character addition of Sergeant Cuff in his 1868 novel, The Moonstone, serialized in ATYR. In doing such, Collins created a fictional companion piece to all of Dickens’s informational articles which attempted to normalize the new investigative tactics of the Detective Force at a critical moment in time in order to pave the way for their acceptance by the Victorian public.
As Mary Elizabeth Leighton and Lisa Sturridge note, “The Moonstone, of course, scrutinizes not only ‘whodunit’ but which power structures and ideological assumptions underlie social acts of investigation.” Upon entering the Verinder house, Sergeant Cuff embarks on an investigative course of action that would have been unfamiliar, and possibly shocking, to the average Victorian middle-class reader. Once he has ascertained the circumstances of the case from Superintendent Seegrave, the officer first called to the scene, Cuff declares his intention to “examine the wardrobes of everybody – from her ladyship downwards – who slept in the house on Wednesday night.” Cuff initially appears to be disturbing the social “power structures” of domestic order by cataloguing the occupants of the Verinder house as ideologically “equal” in his investigation. However, Collins soon provides the reader with a logical and reasonable explanation for such behavior. The prior officer, Superintendent Seegrave, has bungled the initial handling of the case and antagonized the servants by his immediate assumption of their guilt and subsequent search of only their rooms. Sergeant Cuff, in order to win back their cooperation, goes on to explain his plan as “a mere formality…but the servants will accept it as even dealing between them and their betters.” Thus the reader understands Sergeant Cuff is actually restoring the socio-political domestic order that has been upset by Sergeant Seegrave. Indeed, Sergeant Cuff’s plan works so well that the reader is shown how the servants, “instead of hindering the investigation, make a point of honour of assisting it” instead. 
During his tenure at the Verinder house Sergeant Cuff has to sensitively navigate not only these implicit social boundaries of the Victorian domestic sphere but also their physical embodiment within the home’s spaces, which have their own politicized meanings. In Time, Domesticity, and Print Culture, Maria Damkjaer reminds us of “the functional subdivisions within the [Victorian] home [and] the politics of who goes where.” What Damkjaer refers to here is of course the literal and metaphorical “upstairs/downstairs” divides between masters and servants within a Victorian household. In The Moonstone, Sergeant Cuff breaks these typical boundaries through his ability to move freely about the house—upstairs and downstairs—at will. Collins shows Sergeant Cuff seamlessly transitioning from a downstairs dinner with the Verinder servants in one scene to an upstairs meeting in the study to discuss investigational strategy with Lady Verinder in the next. Throughout the initial stages of the investigation, the reader encounters him occupying a variety of different spaces within the house—sleeping outside Rachel Verinder’s upstairs bedroom, lingering in downstairs garden to keep tabs on Rachel’s movements through her bedroom window, and passing silently, almost ghost-like, through the passages of the house to monitor the whereabouts of both servants and gentility. Taken out of context, ATYR’s middle class readership may have found these instances eerily reminiscent of servants spying on their masters (i.e. Mrs. Sparsit with Louisa Bounderby in Hard Times and Mrs. Powell with the titular character in Aurora Floyd) rather than the behavior of a professional detective in the midst of an investigation. Collins’s characters are likewise affronted by Cuff’s lack of respect for the ideological boundaries embedded within the physical domestic spaces of the Verinder home. At various points in the investigation—indeed at various physical points in the house—he is met with anger, disapproval, and even defiance by other characters in the face of his seemingly intrusive actions.
However, Collins once again flips the disapproval of the reader towards Sergeant Cuff by proving the detective methods of his modern officer justified with regard to his liminal movement through the physical spaces of the Verinder home. During the investigation it becomes apparent to both the reader and other characters in the novel that Sergeant Cuff’s suspicions center around one person—Rachel Verinder. Cuff is, after all, often found by the reader to be continually crossing into both upstairs and downstairs of the house in order to track Rachel’s whereabouts and movements that he might find another clue or gain further insight into the mystery of the missing diamond. Once Collins reveals to the reader that Rachel has known exactly who stole her diamond all along, he proves Sergeant Cuff’s suspicions of her withholding valuable information on the whereabouts of the Moonstone entirely correct, even if “circumstances had fatally misled him” as to the cause of her actions. Thus, his inclination to follow her was based on meritorious investigative reasoning. If Rachel had only cooperated with Sergeant Cuff’s earlier and allowed him access to both herself and her rooms, the entire mystery of the novel could have been solved much sooner—Rachel, having named Franklin Blake as the thief would have brought his lack of memory at stealing the diamond out into the open immediately, forcing Dr. Candy to admit his experiment with upon Blake that night while still in full possession of his faculties. Here, both the reader and Rachel learn that she could have spared both herself and the other characters a great deal of misery and trouble if only modern detective methods had been allowed full authority within the domestic space of the Verinder home.
In The Moonstone, Wilkie Collins “offer[s] an exploration of the way in which…mysteries operated within the complex strands of Victorian culture.” Interactions between Sergeant Cuff and the occupants of the Verinder household at the borderlines of social and political spaces of the Victorian home mirrored the anxieties of ATYR’s middle-class readers that the modernity of detective work would inevitably clash with domestic order. However, as Andrew Mangham previously pointed out, criminal activity was alarmingly on the rise inside the Victorian home, and thus detectives could no longer be shut out of such private spaces. Officers not only needed access to Victorian homes, but also acceptance of their modern investigation methods from the families that dwelled within them. The Kairos of necessitating cooperation between detective and domestic in the 1860s prompted Collins to create the character of Sergeant Cuff, and the specific unfolding of events regarding his investigation of the missing titular jewel in the novel. Wilkie Collins and The Moonstone assured the Victorian public that the modern detective did not need to be seen as an enemy of domesticity but rather as a force, which, while briefly disruptive, would ultimately work to restore sociopolitical order to a domestic space that had been disrupted—not by himself, but by the crime he works so tirelessly to solve.
 There have been long-standing disagreements amongst scholars as to which genre of novel The Moonstone belongs. T.S. Eliot memorably claimed The Moonstone as “the first, the longest, and the best of the modern English detective novel” in his 1928 introduction to the Oxford World Press edition; Dehn Gilmore makes the case that contemporary Victorian reviewers and critics branded it an “enigma” or “puzzle” novel in “‘These Verbal Puzzles’: Wilkie Collins, Newspaper Enigmas, and the Victorian Reader as Solver”; Mary Elizabeth Leighton and Lisa Surridge vacillate in their article “The Transatlantic Moonstone” between the “sensation” and “detective” label (see page 217).
 Thomas, quoted in Mangham, “Wilkie Collins (1824-1889).”
 Wynne, The Sensation Novel, 3.
 Dickens, “The Modern Science of Thief-Taking,” 368.
 Sergeant Jack Whicher was fictionalized in Dickens’ articles as Sergeant “Witchem,” and many of his exploits were published in HW. Both Sergeant Whicher and his most famous case, the Road Murder, furnished Collins with inspirational details for the writing of The Moonstone. Mangham, “Wilkie Collins (1824-1889).”
 Leighton and Surridge, “The Transatlantic Moonstone,” 224.
 Collins, The Moonstone, 118.
 Damkjaer, Time, Domesticity, and Print Culture, 2.
 Collins, The Moonstone, 183, 184.
 Mangham, “Wilkie Collins (1824-1889).”
Collins, Wilkie. The Moonstone. Edited by Sandra Kemp. London: Penguin Books, 1998.
Damkjaer, Maria. Time, Domesticity, and Print Culture in Nineteenth-Century Britain. Basingstoke: Palgrave Macmillan, 2016.
Dickens, Charles. “The Modern Science of Thief-Taking.” Household Words 1, no. 16 (July 1850): 368-72.
Leighton, Mary Elizabeth and Lisa Surridge. “The Transatlantic Moonstone: A Study of the Illustrated Serial in Harper’s Weekly.” Victorian Periodicals Review Vol. 42 No. 3 (Fall 2009): 207-43.
Mangham, Andrew. “Wilkie Collins (1824-1889).” A Companion to Crime Fiction. Edited by Charles Rpezka and Lee Horsley. Blackwell Publishing, 2010. Blackwell Reference Online. Accessed 24 October 2016.
Wynne, Deborah. The Sensation Novel and the Victorian Family Magazine. New York: Palgrave Macmillan, 2001.