This paper examines the concept of a future „theatre of contingency“ in the context of extended realities (XR). Building on Janet Murray's vision of the „Holodeck“ as an immersive narrative space and various theatre-historical concepts, the article demonstrates how XR technologies enable new forms of theatrical experience in which spectators become active participants. The contingency theatre utilizes the openness and mutability of virtual reality to explore the boundaries between representation and participation, between fiction and reality. Besides the artistic and narrative potentials, the technical and ethical challenges are also discussed, as well as practical examples showing how XR technologies are already enabling new forms of theatre today. Contingency theatre is presented as a forward-looking approach that not only expands traditional understanding of theatre but also opens up new avenues for collective experiences and societal self-reflection.