Since the digital revolution, media studies has repositioned celluloid in media archaeology while drawing attention to new media, new visual, and new spectatorship. We could then conceive 'what is/was cinema?' by 're-placing' rather than replacing such film theory concepts as apparatus, image, and subjectivity in a feedback circuit between past and present. In this context, the new media term interface seems inspiring; its notion of contact surface between humans and/or machines has evolved in various ways to redefine cinema, screen, and body. But I find interfacial elements or aspects to be inherent in film (studies), given the term's specificity (compared to 'apparatus'), flexibility (applicable to 'sur/face'), universality (implying 'relationality''), and intermediality (rooming 'interdisciplinarity'). A creative adaptation of interface could then serve to discover and invent a synthetic, multi-faceted notion of interfaciality that seems to underlie both image and subjectivity. For this project, I rearticulate a variety of film and interdisciplinary theories such as ontology of image, narratology of material, psychoanalysis of the real, phenomenology of body, cognitivism of mind, ethics of the other, aesthetics of appearance, and sociology of the digital. Ultimately, I propose to remap film studies through the prism of this interface theory. I introduce cinematic interface as any contact surface mediating two sides through spatial difference (object/medium/subject) and temporal deferment (recording/editing/projection). Then, the cinematic apparatus appears as a conveyer belt of interfaces from the single surface (object) through the triple medium-interface (camera/film/screen) to the double body-interface (eye/mind). This model allows us to combine Sigmund Freud's and Henri Bergson's still resonating ideas on perception and memory in a way of reshaping the former theories of apparatus, ideological or analytical. Drawing on a wide range of films, five chapters then investigate the interfaces on screen: (1) the direct appearance of a camera/filmstrip/screen, (2) the character's bodily contact with such a medium-interface, (3) the object's surface and (4) the subject's face as 'quasi-interfaces,' and (5) image and subjectivity as such. In each chapter, interfaciality leads us beyond its basic notion of neutral mediation or transparent communication toward the inherent disequilibrium, intrinsic dialectics, inhuman dimension, and implosive dynamics between two sides of an interface, between object and subject. I elaborate on these inner qualities in terms of ''asymmetrical mutuality,' 'ambivalent tactility,' 'immanent virtuality,' 'multiple directionality,' and 'para- index'/'indexivity'--- five keywords correspondent to five crucial concepts in film theory: suture, embodiment, illusion, signification, and indexicality , which I continue to reframe through different methodologies, unearthing hidden niches and latent constellations between them. Opening with Michael Haneke's Cache, Chapter 1 not only argues that its video-interface 'desutures' classical seamless narrative, but also locates the multiple suture/desuture dialectics in semiotic suture theory, renewed psychoanalysis, enunciation theory, narratography, etc. This process then leads to interfaciality not just before, but also immanent in the eye asymmetrically related to the inhuman Gaze in matter, while moving from the Lacanian to Deleuzian ontology of perception. Likewise, Chapter 2 takes Rossellini's Virginity as a springboard for rethinking the touch of the screen in the history of spectatorship theory: from psychoanalysis through early Rube film study to phenomenology of embodiment. Ambivalently tactile, embodied interfaciality is here found in the skin in terms of 'screen as body' and 'body as screen.' Chapter 3 examines how the surface of an object can appear like a pseudo-camera, a virtual filmstrip, and a flat/fluid/fluorescent screen, as suggested in Apichatpong Weerasethakul's Syndromes and a Century. Questioning the aesthetics of illusion, I here shed light on illusion of interfaciality immanent in the world, the cognitive effect of 'as if it is becoming interface.' On the opposite side, after looking at Kim Ki-duk's Time, Chapter 4 analyzes how the face can function as a multi-directional interface: a 'readerly window' to the character, a 'writerly mirror' for the viewer, a 'machinic simulacrum' of asubjectivity, and an 'uncanny icon' toward otherness. I accordingly trace the notion of signification from semiotics to phenomenology to ontology to ethics. In the final chapter I readdress indexicality in two ways: the image as 'para-index' that only partially, impossibly indicates the absent but immanent Real, and subjectivity as 'indexical activity,' the act of indication for information or participation through our digits' tactile experience of digital interfaces. In this way, my upward trajectory from the infrastructure of apparatus through the superstructure of onscreen images to the apex of image itself goes back down to the actual ground of interface, geared up to our new media world. In so doing I suggest that interface might serve for a general theory of image and subjectivity through a meta-critical reengagement with film theory.