在蓋曼（Neil Gaiman）第一部小說《無有鄉》（Neverwhere, 1997）裡，透過對地下倫敦的想像，挖掘蟄伏於城市之中的邪惡、混亂與時空的交錯。主人翁理查（Richard）地下倫敦之旅顛覆他對城市既有的認識，城市不是如表面所見的井然有序、善惡分明，而是過去與現在的混雜和交織，惡勢力隨時匍匐其中。本文擬以空間議題為經、城市居民主體為緯，探討蓋曼筆下的倫敦呈現何種後現代都市空間、城市空間和主體間的互動，以及游牧主體如何在他者空間中生成。 論文第二章主要藉助索雅（Edward W. Soja）第三空間（thirdspace）的概念，闡釋小說裡後現代倫敦空間。首先爬梳瑞本（Jonathan Raban）、列斐伏爾（Henri Lefebvre）, 和索雅三人對於後現代地理學的觀念，而後側重於索雅提出的第三空間。《無有鄉》裡，城市遠比理查所認為的還要複雜、失序，他漫遊於地上倫敦和地下倫敦之間，其所見景象呈現倫敦浮世繪，解構真實倫敦和想像倫敦間的界線，而此正體現索雅所謂的第三空間。 第三章以班雅明（Walter Benjamin）對漫遊者（flâneur）的討論為出發點，闡釋《無有鄉》裡漫遊者／偵探和城市空間的互動。身兼漫遊者和偵探的理查，由於處在混雜猶如迷宮的倫敦市景中，所以喪失經典漫遊者對城市全景的掌控。雖然《無有鄉》在情節的過程裡呈現後現代氛圍，企圖解構二元對立，但惡勢力最終的剷除，暗示地下倫敦又將回歸秩序，於焉似又陷入善惡二元對立的局面，但另一方面，女性在回歸秩序的過程裡，扮演舉足輕重的地位，女性的參與展現對空間父權化的抵制，而此也打破性別空間的二分法。 第四章著重討論小說的結局。筆者援引德勒茲（Gilles Deleuze）和瓜達里（Félix Guattari）游牧學（nomadology）的概念，闡釋主人翁主體的變異。在他者倫敦空間裡，主人翁和他者接觸而歷經生成他者（becoming-other），並開啟其逃逸路線（lines of flight），所以在回到原本的世界後，他又欲重返地下倫敦，擺盪於兩個世界，不囿於其中一方。 在《無有鄉》裡，兩個倫敦空間並非截然劃分，卻是相互滲透交織。想像的地下倫敦是一個暗喻，代表被城市邊緣化、他者化而忽略的空間，透過主人翁的漫遊，展現倫敦市景的多重面貌。 / Neil Gaiman’s first novel Neverwhere (1996) depicts an imaginary London Below which exposes the urban evil, chaos, and juxtaposition of diverse spaces. After his journey to London Below, the protagonist Richard changes his view of the city. That is, London is not of orderliness as it appears, but of the present interwoven with the past; it lacks a clear distinction between good and evil, and contains evil power embedded underneath. This thesis employs a spatial perspective as a thread to explore postmodern spatiality embodied in Gaiman’s London cityscape, the interaction between urban space and the subject, and the formation of nomadic subjectivity in the spaces of the other. In Chapter Two, I resort to Edward W. Soja’s conception of Thirdspace to deal with postmodern London spatiality in Neverwhere. I first introduce three spatial critics’ notion of postmodern geographies, including Jonathan Raban, Henri Lefebvre, and Soja whose Thirdspace serves as the main spatial framework of the thesis. Neverwhere delineates the urban landscape which is far more complex and disorderly than Richard assumes. He strolls between London Above and London Below, and his view of these two worlds which deconstructs the line between the real and the imagined presents Thirdspace in Soja’s term. Chapter Three utilizes Benjamin’s discussion of the flâneur as a starting point to deal with the interaction between the flâneur/detective and urban spatiality. As a flâneur/detective, Richard encounters labyrinthine cityscape, so he loses a classical flâneur’s/detective’s panoramic view of the city. Although Neverwhere as it progresses smacks greatly of postmodern aura by deconstructing dualisms, the collapse of evil power near the end of the novel suggests the retrieved order, so the novel seems to regress into dualisms. Simultaneously, in the process of regaining order, females play an important role, for females’ participation presents their resistance to patriarchal space and also subverts a gendered spatial dichotomy. Chapter Four focuses on the discussion of the ending of the novel. I apply Gilles Deleuze and Félix Guattari’s conception of nomadology to the protagonist’s nomadic subjectivity. I argue that the other London spatiality triggers the protagonist’s becoming-other via the contagion of the other and initiates his lines of flight. Because of this, after returning to his previous world, the protagonist seeks to leave for London Below. He keeps vacillating between the two worlds, for he refuses to be bound by either of them. In Neverwhere, the multifarious facets of London cartography are outlined through the protagonist’s strolling. The imagined London Below is a metaphor which represents marginalized, otherized and overlooked urban spatiality. The line between London Above and London Below is not completely clear-cut, but interwoven with each other.