This episode investigates the disappearance of Julie Reilly, a 47-year-old mother of one who was reported missing in March 2018. After an extensive four-week-long search fails to find her, the skilled investigators of Police Scotland's major investigations team take up the case. A set of suspicious circumstances and a horrific forensic discovery lead them to a suspect. The detectives now need to find Julie's body and gather enough evidence to charge and ultimately convict him.

Forty-six-year-old Stephen Wallace is found dead in his Paisley home from a number of injuries. The detectives forensically comb the crime scene for clues which will lead them to his killer.