The show's producers claimed that before each series they tested 70-75 psychics and mediums in New Zealand and Australia with a case that had already been solved. (As claimed during each aired episode.) The most accurate psychics were then shortlisted from which the producers chose two or three of them to attempt to contact the spirits of the murder victims and to get impressions helpful to describe the victim, their circumstances around the murder, and the details of their death (as stated by the featured psychics during each episode). The three that were most often chosen (for all the episodes to date) are Deb Webber (Australian) and Sue Nicholson and Kelvin Cruickshank (New Zealanders).