With advanced technology there are new possibilities to interact in virtual environments. Game players are being given more and more new opportunities to intervene as avatars in what is happening in the game, take on roles, and alter the flow of the stories. Through the interaction of many users new storylines and plot constructs are developed, which demonstrate many typical characteristics of modern dramas which are performed in real theatres – the plot is, for example, non-linear and attention is no longer paid to uniting time, place, and plot. These digital “performances” differ greatly from plays performed on real stages, however they are programmed as computer games with the result that the plot must fit into a pre-defined interaction pattern. The players are not casted like real actors. They step out onto the virtual stage as non-trained avatar actors and apart from the usual help options there is initially no director to instruct them. Also, the actions of the virtual actors are not foreseeable and the stories told have no distinct dramatic composition. One of the challenging problems of tomorrow’s iTV is how to generate a digital drama that looks like a real movie but which emerges out of the interaction of many users. The problem of actors’ credibility has been widely discussed in the relevant literature, however only in the context of the traditional theatre play. This chapter describes the concept of a future digital drama and investigates some fundamental aspects of acting in digital environments. The focus is put on the “competitive acting”, a new paradigm for digital stage plays of the future which combine drama with interaction-driven dialogue and action elements in converged media.