This thesis investigates the action films of Johnnie To’s production company Milkyway Image, which has been a leader in Hong Kong cinema over the past two decades. Situating Milkyway’s body of work as a historical allegory in an age inundated with crisis and depression, in terms of both Hong Kong society and Hong Kong cinema, the thesis focuses on the ideological and poetic analysis of Milkyway based on its philosophy of anitya (impermanence). The thesis contains six main chapters. The first three chapters on thematization, narrative forms, and visual styles constitute the analytical poetics of the thesis. I first locate the unitary theme of Milkyway as “running with anitya,” which is realized through the process of staging an interplay between traumatized characters, on the one hand, and post-1997 jianghu as a destiny-machine, on the other. Second, I examine the efforts of Milkyway filmmakers to articulate the narration of anitya by deploying such narrative forms as segmented plotting with a unitary motive, multiplying protagonists, and the network narrative, which refine the episodic narration that characterized traditional Hong Kong cinema. Third, I argue that Milkyway films have consistently displayed two distinctive stylistic trends: visual surrealism and urban realism. The power of visual surrealism lies in a kind of spatial defamiliarization that distorts the daily appearance of locations and drives the destructive power imposed by the machine-like jianghu towards the subjects to the films’ visual surfaces. Eschewing visual extremes and ornamentation, urban realism involves shooting locations that present the cityscape of Hong Kong, mainly in daylight, as the backdrop for the characters’ interactions in a manner that is simultaneously sparing and dynamic. As a study of historical poetics, the following two chapters investigate the reconfiguration of wu (martial arts) and xia (Chinese knights), which are the two basic parameters of Hong Kong action cinema. Chapter 4 situates a crucial contribution of Milkyway in the genealogy of gestural performance of Hong Kong action cinema, that is, the stagnant gesture of a traumatized subject achieved through the composition of bodily silence and stillness. Shedding light on the relationship of Milkyway films to the very tradition of Hong Kong action cinema, chapter 5 scrutinizes Milkyway’s reconstruction of xia and describes it as a practice of critical nostalgia that operates in the dialectical tension between irony and post-ironic solidarity. Finally, I propose “transborder assemblage” as a key conceptual framework to examine Milkyway’s recent co-production films with Mainland China. Overall, the thesis provides a comprehensive and reflective account of Milkyway action cinema by examining its social-politic articulations, narrative forms, visual styles, intertextual relationships with the Hong Kong film tradition, and transborder co-production practices.