In a small rural town in Ireland, Sergeant Gerry Boyle, an eccentric and unorthodox local police officer, leads a somewhat mundane existence marked by his dry wit and disregard for authority. His routine is disrupted when a drug trafficking ring starts operating within his jurisdiction, prompting the arrival of FBI Agent Wendell Everett. Despite their differing approaches, Boyle's irreverence and Everett's by-the-book demeanor, they are forced to collaborate to tackle the growing criminal operations threatening the quiet town.

As they investigate, Boyle's unusual methods and sharp instincts begin to unveil clues about the drug operation, leading to a series of confrontations with local criminals. Alongside this, their partnership evolves as they navigate cultural misunderstandings, personal misgivings, and moments of unexpected camaraderie. Their investigation uncovers a web of corruption and deceit that challenges Boyle's blunt manner and Everett's professional tenacity, setting the stage for an unexpected alliance against the odds.