Philip Glass (b. 1937) composed several works in the 1980s involving elements of film and opera. In the ensuing decade, he continued to explore new means of expression targeted for the stage. The operatic works that comprise his “Cocteau trilogy” reflect this ongoing focus. This thesis analyzes how Jean Cocteau’s earlier films are altered in Glass’s operas, focusing on the role of music in the process of adaptation. As case studies, I explore Orphée (1992), a straightforward operatic production adapted from Cocteau’s 1950 film of the same name, and La Belle et la Bête (1994), an opera for ensemble and film adapted from the 1946 motion picture. / The methodological frame is rooted in Linda Hutcheon’s theory of adaptation, which centers on conceptions of genre in the process of change. For adaptations from film to opera, Hutcheon’s theory offers two important terms that reflect her “dual-vision” in defining adaptation: “product” and “process.” Applied to Orphée and La Belle et la Bête, this model offers fresh insights into Glass’s creative approach. Insights relating to Orphée include (1) the reconstruction of the film’s dramatic structure in the opera based on the original cinematic scenes, (2) the accentuation of important scenes in the opera, and (3) musical allusions that create historical layers between the source texts and the adaptation. Discussion of La Belle et la Bête targets its hybrid performance form as well as recurring motifs that unveil aspects of Glass’s re-interpretation of the well-known fairy tale.Following Hutcheon’s framework for approaching cross-genre transitions, I contend that the process of adaptation in Orphée and La Belle et la Bête points to intertextuality as a central feature of Glass’s compositions from this period. / 菲利普‧格拉斯（b. 1937）于上世紀80年代創作了涵蓋電影和歌劇元素的作品，並于接下的十年中陸續探索新的舞台表現形式。由歌劇作品組成的“尚高克多三部曲”(“Cocteau trilogy”)正是這一主題的重要體現。此論文通過對音樂在改編過程中的角色變化以分析由高克多早期電影至格拉斯的歌劇的體裁轉換。與直接由高克多1950年的同名電影改編而成的歌劇《奧爾菲》(Orphée)一樣，根據與其1946所拍的《美女與野獸》(La Belle et la Bête)同名的歌劇亦是本文的研究案例。 / 本論文的理論框架來自琳達‧赫琦安(Linda Hutcheon)的改編理論。她的理論主要關注“體裁”(genre)這一觀念在改編過程中所發生的變化。對於由電影改編至歌劇的議題，赫琦安提供了兩個重要的理念：“製成品”(product)與“過程”(process)。這兩個概念反映了她在定義“改編”(adaptation)這一理念中所涉及的“雙重視覺”(“double-vision”)。在分析《奧菲斯》和《美女與野獸》的過程中，此模式為分析格拉斯的創新性改編提供了全新的分析視角。通過借助赫琦安的理論，《奧菲斯》體現出以下幾點：（1）電影的戲劇結構基於原電影段落基礎上的重建；（2) 對於歌劇中重要情節的突顯；(3)使用音樂指涉用於揭示原文本與改編文本中的歷史層次。尤其對《美女與野獸》而言，其後現代的表演方式和再現動機的運用揭示了格拉斯對此童話的重新演繹。根據赫琦安在關於跨媒介轉換中所提出的規則，我認為格拉斯的《奧菲斯》和《美女與野獸》的改編過程足以證明了互文性是為格拉斯于此創作時期的主要特點。 / Liang, Danni. / Thesis M.Phil. Chinese University of Hong Kong 2014. / Includes bibliographical references (leaves 93-98). / Abstracts also in Chinese. / Title from PDF title page (viewed on 12, September, 2016). / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.