The work of the British theatre company Blast Theory explores intermedial dramaturgies that this thesis claims can be categorized as radical because they present a generative characteristic. Intermediality, understood here as the impact of analogue and digital technologies in theatrical performance, establishes complex relationships between physical and virtual spaces, structures that create a rich polyphony of multiple temporal orchestrations, and narratives that present a multiplicity of performative arrangements. Intermedial performance, as a performative and experiential event, encompasses a triad of performative interactions between performers, spectators and the media itself executed at and concentrated on the moment of the performance encounter. This research argues that this encounter displays a generative character – a moment at which all the attending performance variables come together in a constant process of performative re-activation thus generating the intermedial performance event. Within this descriptive parameter, this research claims that recent performance conceptualizations fail to account for the work of Blast Theory. Contemporary performance and liveness debates focus principally on the ontology of performance. So, notwithstanding their differences, performance theorists such as Lavender (2002), Fischer-Lichte (2008), and Schechner (2003), and presentness/presence theorists such as Phelan (1993) and Power (2008) all agree that performance is an ontological, ephemeral, and fleeting event. While there are many valid points in these diverse approaches, they only offer a partial account of the specificities of the work of Blast Theory and, by extent, the intermedial performance event. This thesis therefore relocates the terms of the debate on a constructivist epistemological basis. In this way, the thesis proposes that an intermedial performance event must be understood beyond the ontological approach by specifically interrogating the conditions of intelligibility; that is, its operative and intelligible architecture of attending elements and the participating subject. The key hypothesis shared is that in introducing a constructivist reading of epistemology, as described by Alfred Whitehead and Gilles Deleuze, a new account of intermediality in performance emerges as a radical dramaturgy, incorporating generative aspects, and with this, a unique type of intermedial performance subjectivity is enabled.