The irrepressible Jack Hodgson, a talented forensic scientist, joins the team as head of a new forensics department. Jack joins Nikki as she investigates the murder of a pub landlady. Her husband Roly is the prime suspect, but as Nikki and Jack piece together evidence, inconsistencies lead Nikki to believe Holy is innocent. Elsewhere, Leo, Nikki and Jack find themselves in war-torn Afghanistan to identify a body thought to be that of a British soldier who went missing five years earlier.