This study starts off with abrief discussion on how the mystery novel was settled in the realities of the literary world of the 1930s, and how such novel could attract readers and keep them interested. At that time, the popularity of mystery novels was made possible by both internal and external conditions,the collapse of realism novels in accordance with the disorganization of the KAPF, the tendency among readers to prefer entertainment, the popularity of bizarre codes, and the enormous publication of popular novels and complete works series are the external causes. The fact that novels focused on satisfying indirectly the desires for violence and for escape from the current reality that were prevalent among readers is considered as the internal cause. In such an analysis, it was necessaryto decide whether the role of mystery novels at that time could be limited to the tendency to follow the Western style, or the tendency to follow entertainment solely. This paper understands the need to check such tendencies in the 1930s from different perspectives. To facilitate this, this study considered that it is worth finding the meaning of 'reversal', and the 'inversion of value' which are hidden in the fantastic factors that mystery novels have. In line with this, feature-length mystery novels written by famous authors in the 1930s were analyzed. First, “Yeoma”, written by Chae Man Sik, tells about ‘the incident on a cut of a finger’ that was committed by a past grudge, describing the fight between Baek Yeong Ho and mysterious criminals. The novel ended with the punishment on Seo Gwang Ok, who is the mastermind behind all crimes. In this novel, the Lumpen, Baek Yeong Ho, spends his life in luxury, but is negligent and is like a log. He is the trouble-solving broker and is somewhat of a private detective. He is the person who metaphorically exhibits the miserable reality that intellectuals are facing in the era of Japanese imperialism. Though he looks romantic and fantastic, he serves to present the author’s desireto reflect the suppressed reality in the novel. Further,the author expresses an unconscious desire toward what is devilish portrayingSeo Gwang Ok, a wicked woman, and Lee Hak Hee, who is described as a wise mother, good wife and amodern woman. The author is secretly dreaming tooverturn the existing social order through Seo Gwang Ok, the modern woman. However, the author chooses Lee Hak Hee, which reveals the author’s limits by accepting the exiting order. “Beyond the Horizon”, written by Kim Dong In, tells about the venture that an executive member of the Nationalism Party, Seo In Jun is fronting with the LC Party and Lee Phil Ho over the public debt of Count Yoon. The intellectual, Seo In Jun, confronts himself justifiably against the social order kept by Japanese imperialists and the notorious criminal syndicate. Thus, Seo In June satisfies the nationalistic fantasy and related ‘reversal’ at the same time. The modernistic style that Seo In Jun and Miss Yeong represent is just the yearning and imaginative illusion to the general public. In addition, the entity of the Nationalism Party is not so clear, which just shows the illusion of the story. Nevertheless, the author’s intention to express nationalism using nationalistic sensibility serves to facilitate ‘reversal or overturn,’ which challenged everyday suppression at that time, evoking thrilling feelings to the general public. Lastly, “Main”, the feature-length mystery novel, is written by Kim Nae Seong, who is known as the representative author in the modern mystery novel circle. In this novel, Yu Bul Ran, whose job is a detective who pursues the western style, solves the complicated and difficult incident one by one. The repeated reversal in this novel adds to the fun. The grotesqueness and strangeness toward the artists amid the exotic manners and customs stimulates fear along with the artists’ criminal act. Femme fatale, Ju Eun Mong, who is in the middle of the crime, changes into the lily-white girl at the conclusion of the novel, covering fears caused by the confusing and reversed reality. Instead of Ju Eun Mong, who inevitably committed crimes to work offa grudge in the past, Oh Sang Eok, who committed crimesfor money, is ultimately punished for his crimes. Such a conclusion reveals that itis a kind of recipe of the author who knows what readers want. Readers want a happy ending and they do not want uneasiness, e.g. a complete ‘reversal.’ However, such conclusion shows the limits of the author at the same time. As we have seen in the above three works, mystery novels in the 1930s reveal the meaning of fantasy and reversal mainly through women, intellectuals, western-style hobbies, and artists. Gorgeous, but grotesque and strange fantasy attempts reversal, revealing the hidden intention and challenging the existing order. These mystery novels, which comprise a kind of popular novels loyal to the desire of the general public, try not to reveal the meaning of ‘reversal’ in any way. However, the authors’ attempts to do so seem incomplete. It is for this reason we can still find uneasy and bizarre things in the novels.