Most existing authoring systems for wearable augmented and virtual reality experiences concentrate on creating separate media objects and embedding them within the user's surroundings. In contrast, designing narrative multimedia experiences for such environments is still largely a tedious manual task. We present an authoring tool for creating and editing 3D hypermedia narratives that are interwoven with a wearable computer user's surrounding environment. Our system is designed for use by authors who are not programmers, and allows them to preview their results on a desktop workstation, as well as with an augmented or virtual reality system.