When her career is threatened due to a series of undue force allegations, DI Fia Lucey is sent back to her hometown of Blackwater to investigate a missing person case.

With the case now confirmed a murder, Fia suspects her new partner, Detective Furlong. But she soon discovers the dark secrets of the town have their roots in a more powerful source.

The murder victim's daughter is missing, and Fia is in a race against time. A press conference erupts into allegations of her father’s involvement in another case 20 years ago.

As the past and present begin to merge, Fia uncovers the truth behind the abuse of a number of young women in the town. But the discovery of a body in the lake – there for over 20 years – points to a deeper and darker collusion in the town.

The Blackwater Whiskey Festival has arrived, and it appears that the Roisin Hurley case has been solved. However, Fia knows there is more to this story. With her partner, Cian Furlong, now firmly on her side, Fia takes the law into her own hands in order to get to the truth.

Fia is still struggling to find the evidence she needs to bring the case to a close. With her case at a standstill, she is unsure if she can confirm what she knows to be true.