The golden age of radio plays was in the 1950s. How young people experienced radio plays back then—without television, without earphones, without audiobooks—can be read in this book, as it contains a study conducted during that time. The twenty-year-old listeners who participated in this study observed themselves: how they imagined interiors, street scenes, and landscapes, portrayed villains, heroes, and couples in love, and how they explored their bodily sensations and moods. The publication of these self-observations was suppressed by radio bureaucrats at the time because knowledge was considered dangerous. Only the Graz studio did not share this fear, and inspired by subsequent conversations with the editors and technicians of the station, Friedrich Knilli invented the sound play. It was an application of the research findings published in this book and has remained a challenge to radio play officials to this day.