千禧年之際，尼爾‧蓋曼(Neil Gaiman)這位傑出的天才作家將他的寫作重心從成人文學轉移至兒童文學。蓋曼的兒童小說不僅如同他風靡全球的成人作品，深具文學價值、榮獲多項重要獎項；更重要的是，其讀者群遍及兒童與成人讀者。本論文將從跨界小說(crossover novel)的角度，以蓋曼的兒童小說《第十四道門》(Coraline)及《墓園裡的男孩》(The Graveyard Book)為例，探討雙重讀者(dual readership)現象以及書中成人與兒童流動的權力關係。 本論文分成三部分。第一章探討成人及兒童對此二書愛不釋手的原因。本文主張：跨界閱讀非但不是成人的墮落，更應視為兒童文學的進化。第二及第三章接續前章所指出的特質，探討二本小說當中意義的複雜性及顛覆性。第二章借重巴赫汀(Mikhail Bakhtin)的嘉年華會理論(carnivalesque)，討論書中跨界與歧義的特質如何賦予文本多樣性，推翻傳統認知中典型的兒童小說。第三章則連結嘉年華會理論與兒童文學間的共同特質，揭露書中成人角色和兒童角色之間流動的權力關係。本論文總結認為：以嘉年華會的觀點來看，兒童角色具有撼動成人角色優越地位的能力；但蓋曼的兒童小說雖具顛覆性，卻亦如安全閥般提供書中兒童角色宣洩負面能量的機會，提供成人與兒童角色重新展開和睦關係的新契機。 Neil Gaiman, the outstanding storytelling genius, has switched path from writing adult’s literature to children’s literature in the millennium. Same as his adult’s works, Gaiman’s children’s works are rich in literary issues and have received various notable rewards. They are enjoyed not only by child readers, but also prevailing among adult readers. The aim of the thesis is to place Gaiman’s two children’s novels, Coraline and The Graveyard Book, in the context of crossover novels, exploring the dual readership and dynamic adult-child relationship in the novels. My thesis is divided into three parts. Chapter One explores the reasons behind the appeal of the two crossover novels. Instead of regarding crossover reading as a degradation of adults, the thesis views it as unveiling the advancement of children’s literature in these few decades. The reasons for this dual readership also exhibit the two books’ multiplicity and subversiveness, which are put into further discussions in Chapter Two and Chapter Three, respectively. Chapter Two gives weight to the ambivalence and intricacy of the two novels by applying Mikhail Bakhtin’s carnivalesque. I argue that the non-border and two-faced features in carnivalesque which are also characterized in the two stories subvert the traditional story pattern of children’s literature. Chapter Three connects the Bakhtinian carnivalesque and children’s literature and calls into attention the seesaw relationship between adult and child characters. This thesis concludes that in the novels, child characters possess the power to destabilize the dominance of adult characters. However, as carnivalized texts, children’s novels as such serve as a safety valve for child characters to release negative energies, and as a chance to renew the harmonious relation between adult and child characters.