A convict escapes while being transferred to prison and while trying to track him, the Ashfordly officers uncover a smuggling ring in Whitby. Nick goes undercover at a fish market, while Bellamy's own tactics of finding the convict results in him being taken hostage by a gang of fugitives. Elsewhere, Greengrass enters the fish trading business, Aunt Eileen is reunited with an old flame who makes a life-changing request, while Nick receives the results of his sergeant's exam.