On the evening of Saturday, 19 March 2011, D.S. Stephen Fulcher receives a life-changing call that thrusts him into a race against time to save missing 22-year-old Sian O'Callaghan, who was last seen at a nightclub in Swindon. Steve knows from experience that he has a small window of time to find Sian alive, but his hopes are quickly dashed when his investigation leads him to Christopher Halliwell. Following the investigation as it develops hour-by-hour, Steve's gripping inside story of the cat-and-mouse situation that ensues shows how he hunted down Halliwell - his number-one suspect - which led him to the discovery of Sian's body and another victim, Becky Godden-Edwards, who had been missing since 2002. Catching a Serial Killer is a thrilling, devastating and absorbing look at a real-life murder case and potentially one of the UK's most prolific serial killers.