The heart-wrenching case of eight-year-old Sarah Payne, who was abducted and murdered. A forensic ecologist finds a vital link between the suspect and the gravesite. And an expert witness analyses blood at the scene, where remains are found in a freezer

A twisted killer throws two suitcases containing severed remains into a canal, and it’s down to a 3D-scanning expert to uncover the crucial evidence needed to convict him. And a forensic entomologist helps prove a suspected case of extreme dog neglect.