Antonia Quirke presents a special edition on the thriller. She hears some tricks of the trade from Ronan Bennett, writer of Face, Public Enemies and Gunpowder, who reveals why he thinks thrillers should really be called "tensers". Award-winning editor Walter Murch takes us through a key scene in the classic conspiracy thriller The Conversation and explains how to build paranoia in the audience by embedding subsonic frequencies in the soundtrack. Composer Rachel Portman explains how music can achieve the same effect with the application of low strings and alto saxophone. Alexandre O. Philippe reveals the secrets of the shower scene in Psycho in his new documentary 78/52, including the identity of the painting that covers Norman Bates' peep-hole. Woman In Black director James Watkins reveals how he took screen grabs of fifty of the greatest supernatural thrillers in movie history and dissected their key moments shot by shot in order to learn how to chill the audience to the marrow.