A fatal fire in a holiday let on Slievemore, Achill Island, leaves one person dead and another missing. Deemed arson, DS Lucy Golden and her team are tasked with solving the murder and locating the missing woman, Moira Delaney. As the case develops, the pressure builds when it transpires that Moira's father is a gangland figure, a suspect in three unsolved murders.

If Lucy doesn't uncover what happened that morning in Slievemore, he will deploy his men to deal out his own sort of justice. Things get even more complicated when a laptop is uncovered that could ruin all that Lucy holds dear. And as the net on the suspect tightens, Lucy faces a hard choice - will she use it to save herself and bring a murderer to justice, or bury it and save her family and her career?