It's May Day and the members of a small community go about their business as they wait for this year's parade to begin. But when the May Queen - local teenager Hattie Sutton - fails to appear, several townsfolk are sent spinning by the suspicion that someone among them has taken her.

A devastating discovery throws the spotlight on a key suspect and forces Gail to face unwelcome facts about husband Malcolm. Caitlin and Linus's relationship deepens when she tells him a shameful secret about the day her sister went missing, while Fiona grows suspicious of Everett.

Linus makes a dangerous promise to Caitlin and discovers the true nature of Everett's connection to Hattie. Fiona and Alan come to blows over Charlotte's odd behaviour, while Gail's lack of forgiveness drives a wedge between her and James.

As the townsfolk gather for the memorial, things take a dark turn and a chaotic interruption has fatal consequences. Steve finally gets his moment with Angie - will he manage to win his family back? Fiona must face her old colleagues in a way she never thought she would, Caitlin makes an eerie transformation, and Everett and Linus have a confrontation that takes their relationship to a new level.