An interactive entertainment system enables presentation of supplemental interactive content along side traditional broadcast video prams, such as television shows and movies. The programs are broadcast in a conventional manner. The supplemental content is supplied as part of the same program signal over the broadcast network, or separately over another distribution network. A viewer computing unit is located at the viewer's home to present the program and supplemental content to a viewer. When the viewer tunes to a particular channel, the viewer computing unit consults an electronic programming guide (EPG) to determine if the present program carried on the channel is interactive. If it is, the viewer computing unit launches a browser. The browser uses a target specification stored in the EPG to activate a target resource containing the supplemental content for enhancing the broadcast program. The target resource contains display layout instructions prescribing how the supplemental content and the video content program are to appear in relation to one another when displayed. When the data from the target resource is downloaded, the viewer computing unit is responsive to the layout instructions obtained from the target resource to display the supplemental content concurrently with the video content program. Embedding the layout instructions in the supplemental content advantageously places control of the presentation to the content developers. The developers are free to arrange the data and video in any manner they choose.