The goal of our paper is to demonstrate through artistic experimentation that the concept of montage can be an effective vector for conveying complex narratives in immersive, room-scale virtual reality experiences. We review the particularities of virtual reality mediations regarding narrative, and we propose the new conceptual framework of « spatial montage » inspired by traditional cinematographic montage, taking into account the specific needs of virtual reality. We make the hypothesis that spatial montage needs to be related to body action of the user and can play a significant role in relating the immersive experience with an externally authored narrative. To test those hypotheses, we have built a set of tools implementing the basic capabilities of spatial montage in the Unity 3D game engine for use in an immersive virtual environment. The resulting prototype redefines the traditional concepts of shots and cuts using virtual stages and portals and proposes new interaction paradigms for creating and experiencing montage in virtual reality headsets.