Borderline is a performative piece concerned with time-based and improvisational action, in which two participants interact together within an audio-visual environment to gain a sense of the project’s latent narrative identities. Borderline will re-deploy VJ software technologies (using MIDI with MAX-MSP) to develop a dual interaction experience that uses hand-based gesture (via two graphic tablets and their pens) instead of the established hyperlink model. This will help foster a ‘computer system as instrument’ analogy in which the participants’ can ‘improvise’ ‘play’ or ‘perform’ set of narrative dualities. An often-levied criticism of VJ output is its preference for visual abstraction over content (Amerika 2005). In terms of the narrative, Leishman will both develop a new bank of non-abstract imagery, audio and animation to convey the theme of dualism. This will be based on research into borderline personality disorder (visualizing the problems of disassociation and hysteria through image, movement and narrative structure). Binary character protagonists from popular and literary culture alongside the philosophical notion of the double shadow (Jung, Neumann 1969) will also be used to frame the narrative. The borderline, the point of change between one state and another will be highlighted within the artwork. The two participants can choose to be social: to improvise / play /perform harmoniously together or be antisocial: to be in conflict with both the narrative and indeed with each other. Their expressive actions (for example fast / slow, long / short pen gestures) will significantly affect their narrative agency, immersion and comprehension.