This paper offers an analysis of two different performances: Angst II by Anne Imhof and Les Métopes du Parthénon by Romeo Castellucci, examining how equivalencies between “Theatre” and “Performance” are developed and challenged within the mimesis frame. In particular, it considers that performative theatre, as a specific validity claim of aesthetic form, can only be understood as an artistic code which reaches far beyond the limited realm of the imitation principle. I thus argue that these two performances, although based on non-mimetic logic, create internal theatrical coherence in communication with the audience.