This thesis seeks to explore the use of portals applied in cinematic virtual reality (CVR) as a scene transition method, and to outline some key characteristics of a portal in this context. A 15 minute CVR prototype experience featuring portal transitions, triggered through interactions with a portkey object was developed in the Unity game engine. A user study was conducted with this prototype with the aim to qualitatively uncover dominant subjective perspectives of the portal transition in the CVR context. Two dominant social perspectives, that were termed Voyagers and Observers emerged from this sample. The two perspectives are distinct collective viewpoints, and each participant was sorted into one of these groups depending on the answers they gave in the user study. There was distinguishing opinions between the two collective groups, but also some opinions that were similar between both groups. The interpreted results provide a flexible best practice guideline, with four design principles for portal transitions in CVR narratives. This may be utilised by future directors and content producers of CVR experiences, as well as providing insight for researchers in the field of interactive digital narratives, and cinematic virtual reality.