The design and experience of the location-based performance Uncle Roy All Around You Steve Benford, Martin Flintham, Adam Drodz, The Mixed Reality Laboratory, The University of Nottingham Nick Tandavanitj, Matt Adams, Ju Row Farr, Blast Theory Introduction Since 2001, the artists group Blast Theory and the MRL at the University of Nottingham have created and toured a series of location-based artistic performances. These have mixed elements of computer games and live action to create experiences that are simultaneously accessed by mobile and online participants. The overall aims of this collaboration have been twofold: first, to create professional touring works that both use and challenge emerging technologies; and second, to enable researchers to study these technologies ‘in the wild’ so as to inform further technology development and help them articulate more general design principles. The collaboration between Blast Theory and the MRL dates back to 1996 and the inception of Desert Rain, a theatrical performance that drew its inspiration from the first Gulf War. This took form of a computer game in which six players at a time were sent on a shared mission in a virtual world to locate and identify six targets, people with different connections to and perspectives on the war (Koleva, 2001). Desert Rain was notable for the way in which it combined aspects of computer games with live performance and integrated a collaborative virtual environment into an extensive physical set. In particular, each player experienced the virtual world via their own ‘Rain Curtain’, a two meter by two meter screen composed of water spray into which the image of the virtual world was projected, and through which actors and the players themselves would pass during the performance. Early performances of Desert Rain were subject to ethnographic study, in which social scientists observed players, performers and technical crew, both live and using video recordings, so that they could describe the processes through which Desert Rain was made to work as a performance. This study revealed the importance of orchestration processes and led to proposals for new orchestration technologies (Koleva, 2001) Can You See Me Now? The second collaboration between Blast Theory and the MRL, Can You See Me Now? (CYSMN), introduced a focus on mobile and location-based technologies (Flintham, 2003). Originally created for the Shooting Live Artists festival in Sheffield, UK, in December 2001, CYSMN once again mixed the worlds of computer gaming and live performance. Structurally, CYSMN is simply a game of chase in which members of the public are chased through a city by a team of performers. However, there is a twist; the public players are online in a shared 3D model of the city, while the performers, equipped with handheld computers with GPS receivers and WiFi wireless networking, have to run through the streets of the actual city in order to catch them. As they run, so the performers discuss their tactics and describe the city