Susan interviews a noted arsonist imprisoned in France, Jacques Dutronc, on the psychology of arson whilst both Andy and another fire-raiser, former asylum inmate Miles Van Der Twemp are cleared as having no links to both murders. A new suspect enters the frame, Susan Etchells, who was in the asylum under her mother's name, Susan Winters - the latest victim being a teacher who sacked a woman by that name. Creegan finds that he has to go back to school, literally, to discover the disturbed woman behind the attacks and risk his life to save another victim. (thetvdb.com)