Abstract: Disney Imagineering has developed a high-fidelity virtual reality (VR) attraction where guests fly a magic carpet through a virtual world based on the animated film "Aladdin." Unlike most existing work on VR, which has focused on hardware and systems software, we assumed high fidelity and focused on using VR as a new medium to tell stories. We fielded our system at EPCOT Center for a period of fourteen months and conducted controlled experiments, observing the reactions of over 45,000 guests. Riders filled out an exit survey after the experience, and with select groups we used a number of other data-gathering techniques, including interviews and mechanically logging where guests looked and flew. Our major finding is that in a high fidelity VR experience, men and women of all ages suspend disbelief and accept the illusion that they are in a different place. We have found that in VR, as in all media, content matters. Novices are unimpressed with the technology for its own sake; they care about what there is to do in the virtual world. We can improve the experience by telling a pre-immersion "background story" and by giving the guest a concrete goal to perform in the virtual environment. Our eventual goal is to develop the lexicon for this new storytelling medium: the set of communication techniques shared between directors and the audience. We conclude with a discussion of our second version of the Aladdin project, which contains a large number of synthetic characters and a narrative story line.