She was met at reception by an efficient young man she’d never seen working there before, and guided into a spare office where a computer was ready to play the file. She was offered coffee but refused it, then the door whooshed softly shut and Ava was alone.

Ava pulled out a notepad and pen to record her observations as she went, knowing she would watch the footage a hundred times more before the case was done, but she had to start somewhere. The screen was blank save for a case number in the top left-hand corner. The practice of videoing postmortems had only become common procedure a year earlier in all cases where there was some sign of criminal activity. In this case, the deceased had yet to be identified. Missing persons files had been cross-checked but no one matching the deceased’s description or appearance had been reported missing in the previous six months. Putting a name to the corpse was the number one job on Ava’s list right now. She pressed play and Edinburgh’s Chief Forensic Pathologist appeared on screen, running her fingers over a computer keyboard before glancing into the camera and beginning her work.

‘Right,’ Dr Ailsa Lambert said, snapping on gloves, ‘this young man – identity as yet unknown – is aged between twenty and twenty-five years. Measurements already taken show that he is 5’11” in height, slim build, Caucasian, dark brown hair, hazel eyes. Weight is 178 pounds.’

Dr Lambert pulled back a sheet to reveal a naked body, devoid of the healthy pink colour of life, with a patch of bloody scabs on his upper abdomen. Ava peered more closely at the screen, writing her first question: how old are the scabs?

‘The only externally visible trauma is to the abdominal area. It’s not clear yet if that was caused accidentally or deliberately but there are remnants of butterfly stitches amongst the scabbing.’ Dr Lambert walked towards her computer, unclipped the little camera poised above the screen and walked with it to the body. The viewpoint suddenly switched to first person as a gloved fingertip pointed at tiny white fragments of paper between the scabs. ‘Whatever caused the trauma, medical treatment was given, though it doesn’t appear to be professional. My assessment is that surgical stitches would have been applied at a hospital, and the extent of the scabbing shows that insufficient care was given to fully stopping the bleeding before the butterfly stitches were applied. Nonetheless, an effort was made to assist this young man.’

Dr Lambert shifted position and made her way down to the man’s feet.