The document discusses the effectiveness of the main film "The Call" and its two ancillary texts - a film poster and radio trailer. It aims to create a sense of mystery and unknown for viewers by not answering all questions. Both the poster and radio trailer maintain this feeling through minimal information and slogans that pique viewer curiosity without resolution. Comparisons are made to real advertising products to show how the ancillary texts achieve professional standards in marketing the film's mysterious thriller genre.