Aristotle said:” The object that the theater imitates is the man in action.” This is the objective why the avant-garde theater undoes the classic representation-relation: to get the actor and spectator jumping out of the frame of the stage, in order to become immediately a 'man in action'. But this 'actor without representation', where is he going finally? We try to find his way through Deleuze's two themes of action. Ⅰ. Undoing the representation does not mean a direct participation of action, but rather a crisis of the collapse of action and impotence of thought, however, maybe also an opening towards a certain 'spiritual automat'. Ⅱ. Aesthetic sensation is not action, but pure presence and contemplation. Accordingly, we re-study how the 'actor' in Taiwan avant-garde theater rises from the social-political struggle, and then turns gradually to the ritual and the exercise, in drawing a line of flight towards the horizon of withdrawing and disappearing.