An interactive television system is able to provide an interactive television program having a plurality of video signals related in time and content. The video signals are in a digital format. At a receiving station, a first video signal is selected for display. The system is able to provide a seamless transition when the viewer switches from the display of the first video signal, to the display of a second video signal. Live or pre-recorded programs are stored on an optical disc together with control codes so that on reading the video signals from the optical disc, seamless switching between video signals from the disc, or between video signals from the disc and received from other sources, is enabled. The optical disc may be played by the viewer at his receiving station, or may be played at a central location and the video signals transmitted to receiving stations.