Donegal, Ireland, 1974: After years of quiet living in the secluded coastal village of Cashel, war veteran Finbar Murphy has built a reputation as a gentle and reclusive figure. He’s well liked but lives a mostly solitary life. Apart from two ‘work colleagues’, he is only really close with his elderly neighbour, Rita, and Vincent, the local Policeman, neither of whom know the real Finbar. Cashel is where he hides. During a run-of-the-mill execution, Finbar has an epiphany - it’s time to hang up his guns and tend to his neglected garden. It's time to become the man everyone thinks he is. He cuts all ties with his handler, determined to see out his days as an integral member of the close-knit community. But having judiciously evaded the law for so long, trouble soon finds its way to his door. When a local young girl and her single mother are victims of abuse, Finbar is drawn to action. His ex-handler advises against a hit on his own doorstep, but Finbar is unable to turn a blind eye.