This dissertation examines the role of media and movement in contemporary choreography and film. In contrast to the prevailing critical emphasis on the physical apparatus of new media and technology in performance, it identifies a formal connection between cinema and choreography in a common constitutive element, movement. Like frames in film, the continuous passage of this movement provides a structural alternative to dramatic unity and redirects its audience towards events and possibilities from beyond the boundaries of of the theatrical and cinematic scene- and the visual field of the seen. These peripheral events manifest themselves as a "screen" that diffuses or obfuscates the site- and sight- of performance. Rather than a surface for the projection of images, this screen is the product of continuous motion. This continuous motion consists of two modes, autoimmunity and the ambulatory. The dissertation first considers autoimmunity in Yvonne Rainer's early choreography, which implements a structure based on incessant stopping. This structural intermittence establishes an affinity with film and produces an actual screen, which is embodied on stage by mattresses. In search of relief from this structure of relentless interruption, Rainer's subsequent dance, Trio A, develops another choreographic structure, ambulatory motion. In addition to suspending formal unity, ambulatory motion's pedestrian pace diffuses distinct qualities. Applied to a subsequent study of Chantal Akerman's feminist film je tu il elle, this diffusion becomes a formal category, opacity. By considering je tu il elle with regard to Akerman's recent documentaries on immigrants and autobiographical video installations, it is possible to link feminist performance to translation, which itself instantiates continuous motion. William Forsythe's choreography also uses translation, albeit in a way that returns to Rainer's engagement with autoimmunity as an aesthetic process. Unlike Rainer, Forsythe's translations emphasize autoimmunity's biopolitical aspects, which anticipate a life form that does not adhere to biological or technological definitions and whose collectivity relates to a notion of media that separates what it connects- namely, the screen.