In a life or death situation your first instinct is to ring 999, but will you be making a life saving call? Or a death call? When Crane is convinced there is someone hacking into the 999 emergency call centre in Winchester, he has to convince Anderson and the rest of the team that he's not imagining things. There really is a killer on the loose and Crane has to find him. Not only in the pursuit of justice - but because this time it's personal.