A clever science-fiction thriller which is genuinely thought provoking rather than just visually mind-blowing. On the thirteenth floor of a tower block three men have created an amazing virtual world set in 1937 Los Angeles, but the brutal murder of the project's leader leaves one of the designers, Douglas Hall, as the main suspect. In order to vindicate himself and indeed find out whether or not he is the killer, Hall must immerse himself in the virtual world he has helped to create and attempt to unravel what is real from what is not.