Over the past decades, the theatrical landscape of Brussels has increasingly reflected its multilingual everyday reality on stage. In consequence, today’s heteroglossic productions have propelled various dramaturgic and aesthetic experiments to render the linguistic multiplicity accessible. Current theorizations of the translator’s role in theatrical settings, however, prove inadequate to address the complexity of postdramatic, multilingual and technology-assisted creation processes. The study engages with this hiatus by exposing the underlying agency networks of interlingual, on-stage translations. To this end, it adopts an actor-network theoretical approach. Responding to a bias of research frameworks grounded in translation studies, it examines the field of theatre translation studies through a performance aesthetic lens, to grant due consideration to paradigms from theatre studies. Translation modes in focus are mimetic surtitling, playful surtitling, consecutive interpreting and automated cueing. First analysing how multilingual dramaturgies inform the selected translation modes, the study goes on to propose a reconfiguration of the ‘translator agency’ for each mode. Through a multiple case study of postdramatic performances by Brussels-based companies, the project aims to provide scholars and practitioners with a framework for negotiating multilingualism on stage and to strengthen the nexus between university and arts sector.