Join DI Liam McLaughlin and his team of have-a-go heroes--young upstart DS Nancy D'Arcy, ladies-man-in-his-mind DC Tom Lyons, tech whiz DC Fern Hawkins and newbie DC Henry 'Hens' Cahill--as they grapple with unmasking the most heinous of Derry City's murderers for the Major Investigation Team of the Police Service of Northern Ireland.