When Val Ahern's husband Denis is found dead at a foot of a cliff close to their home the morning after a family party, she begins to interrogate his relationships with his family.
Val struggles to understand Grace's actions, while the local Gardaí look closer at the Ahern family as the investigation ceases treating Denis death as an accident.
Val looks to Mairead for support when Carl comes under fire as events from his past life in Denmark come to light, while Calum has a run-in with a group of local lads.
The Aherns question Calum's recent violent behaviour, while Grace sees Joe for the first time since she confronted him at home. Jenny and Frank reminisce about Denis.
Jenny tries desperately to resolve her financial difficulties, while events spiral out of control at Anna's birthday lunch despite Val's attempts to keep the family together.
Val increases her efforts to find out the truth about Denis’ death, finding herself torn between reality and what is right. Rory makes long-overdue amends and protects his boys.
With the family still picking up the pieces after the death of Denis, a stranger turns up on Val's doorstep claiming to be Denis' estranged son, Finn. Presented with this unwelcome guest, the Aherns soon realise their ordeal is far from over.
Val and her three daughters are stunned to discover the word 'liar' scrawled in lipstick across the mirror. To Val, the ramifications are starkly evident: someone is clearly out to get her.
As the Aherns prepare for Calum's birthday celebrations, they struggle to maintain a semblance of normality as the campaign of terror against the family escalates.
In the aftermath of the birthday party, the family is in disarray. Elaine insists she has been set up but fingers are being pointed in every direction.
Val tries to figure out who she can trust and how she can protect her family from danger, while Finn agrees to help Elaine convince Calum her drink was spiked the day of the crash.
Trying to put her life back together after the tragic events of the last few years, Val has found love with Paul Madigan. Return of the thriller, starring Dervla Kirwan
Jenny and Anna confront Elaine over their sister's death, while an increasingly isolated Val must face up to her own worst fears about Grace when she undergoes therapy.
Paul convinces Val that she has to cut herself off from her family due to their toxic influence, but she struggles to stick to his advice. Jenny and Anna travel to Donegal to investigate Grace's death themselves and they make a shocking discovery while there.
Val refuses to listen to Jenny and Anna's fears that her life is in danger, but when she finally realises what Paul has been hiding, events spiral towards a shocking conclusion.
On trial for murder, Val's fate appears to be sealed as the events surrounding the death are presented to the court and the Ahern family are thrust back into the spotlight. But there may yet be one final twist in this tale.