Cathartic vigilante comedy well-suited to our age of radical moral reckoning

deeply sympathetic guide through the world that writer-director Martin McDonagh creates.

His movie fuses naturalism and hysterically pitched theatricality with sometimes uneasy, but bracing results.

McDonagh, known for such operatically profane, extravagantly brutal exercises as and

stint doesn’t on his signature flourishes:

is as dark as they come, a pitchblack, often laceratingly funny look at human nature at its most nasty, brutish and dimwitted.

But he anneals the cleansing fire with moments of startling tenderness, using compassion to shock viewers the way other directors wield the dark arts of sex and violence.

As the movie opens, Mildred has not yet recovered from the sadistic rape and murder of her teenage daughter Angela, a crime that occurred seven months ago in the small Ozark mountain town of Ebbing.

Spying three decrepit billboards on her way home one day, she hits on an idea to impel the local police chief, William Willoughby (Woody Harrelson), into action: she buys ad space on all three, fashioning a naming-and-shaming campaign asking him why the case is still unsolved.

Mildred’s idea of avenging Angela inevitably has a cascading effect, not only with Willoughby – played with upstanding directness and pathos by Harrelson – but also by his dumb-as-a-rock deputy, Dixon, portrayed in an amusingly scurrilous turn by Sam Rockwell.

Casting vanity to the wind, Rockwell affects an ungainly posture and unflattering haircut to play a racist, homophobic, supremely idiotic mama’s boy drunk on his own blunt-force power.

If Mildred embodies fairness at its most extreme, Dixon is its opposite, a living, breathing symbol of unacknowledged, unearned privilege.

is shot through with stinging, sometimes breathtakingly direct commentaries about racism and policing in a community that even though it’s fictional, lies firmly within the orbit of Ferguson.