Following the unexplained death of a man in Yorkshire, found alone in his home with no signs of forced entry or a struggle, police were at a loss to explain his death. They turned to expert witness Duncan Campbell to help solve the mystery. Duncan, a forensic scientist, decided to analyse something that is part of everyday life, food. After examining the man's final meal, the expert witness not only solved the crime, but in turn helped to make legal history by ensuring a guilty verdict was achieved in this very rare and unusual case.

Sometimes, before a murderer can be identified, the victim must be identified. Such a challenge faced the police when human remains washed up on a beach in Scotland. Detectives enlisted the help of expert witness Caroline Wilkinson to identify the body of the unknown victim. An expert in forensic facial reconstruction, Caroline was able to rebuild the facial features of the young woman. This allowed police to identify the victim and in turn enabled them to catch her killers and put them behind bars.

This episode follows two shocking criminal cases in Yorkshire, each involving a woman murdered by her partner and two expert witness with very different disciplines in forensic science who help to deliver justice.

We often think about crime scene investigations as being about the DNA left behind in traces of blood, hair or skin cells at the site of an attack, but in our first story, it was the site itself, the natural environment, that provided the biggest clue to detectives. A young woman went missing in Hull, and despite an emotional appeal by her partner, he soon became a chief suspect in the missing woman's case. But suspecting who might be the perpetrator of a crime is one thing; proving beyond reasonable doubt that the suspect was responsible is another. Police asked for help from Patricia Wiltshire, a forensic ecologist. The partner of the missing woman initially claimed he had killed her by mistake but couldn't remember where he had buried her body. Patricia was given access to his car and footwear, and was able to use her botany skills to pinpoint where the body of the missing woman was and help prove it was murder.

And in Melsonby, analysis of blood spatter found at a crime scene revealed the truth behind a husband's lies. A woman was found dead in the home she shared with her husband, above a post office. Her husband claimed that she had been held hostage, but this didn't fit the timeframe. The police asked Jo Millington, an expert in blood spatter analysis, for help. Jo showed that the direction of blood at the crime scene meant there may never have been a break in, and the husband was convicted of murder.