Michael (Christopher Abbott), the last son of a farming family, lives an isolated existence with his ailing, cantankerous father Ray. Burdened by a terrible secret from his past, Michael has isolated himself from the world and dedicates himself to his prized flock. When the ongoing conflict with rival farmer Gary and his wayward and unpredictable son Jack (Barry Keoghan) stirs old tensions and grievances, it triggers a chain of events that take increasingly violent and devastating turns, leaving both families permanently altered.