Three Billboards Outside Ebbing, Missouri proves it pays to advertise.

Imagine a world where nothing and nobody adheres to a neatly binary system of good and bad and life is messy and compromised. It’s this real-world untidiness which lies at the beating heart of “Three Billboards Outside Ebbing, Missouri”, Martin McDonagh’s brash, darkly funny and often shocking fable of small-town disenfranchised American life.

Frustrated by the lack of action by the local police department in catching those responsible for her daughter’s brutal murder, Mildred (Frances McDormand) takes matters into her own hands, publicly challenging Sherriff Willoughby (Woody Harrelson) through the use of three simple billboards on one of the back roads of Ebbing.

There’s a devilish simplicity and charm to the way McDonagh allows his story to unfold, exploring the nature of grief, prejudice and the toxic cocktail of entitlement, fear, anger and ideology which is currently consuming America at every level. Packed full of flawed characters, thwarted redemptions and untidy, irrational emotions and actions, the cast lead the audience on a subversively unpredictable waltz of empathy and sympathy.

McDormand is superb as the take-no-prisoners mother turned rebellious vigilante, determined to use every means at her disposal to seek justice for her daughter while Woody Harrelson exudes an abundance of small-town charm and charisma as the deceptively wise and wily Sheriff who’s facing some life-changing issues of his own. It’s in Sam Rockwell’s repugnant deputy Dixon, though, that the film finds its truest expression of itself. It’s a courageous move by both actor and writer/ director to shape a character so thoroughly loathsome only to deconstruct him and almost taunt him, and the audience, with a redemption that the cosy conventions of storytelling would have us believe he has not earned and barely deserves.

It’s this dedication to verisimilitude against every narrative instinct that transforms “Three Billboards” into such a human and humane experience. In grief, there may be pain and suffering and anger but there is also warmth and humour and tenderness. Hatred and vengeance, too, find their roots in that pain and, as an added kicker, justice, as well as being blind, can sometimes be tone-deaf too. Dark, violent, horrifying, uplifting, tender and laugh-out-loud funny, “Three Billboards Outside Ebbing, Missouri” dares to show us, despite the fissures and cracks which riddle the fragile façade of society, there may just be more that unites us than divides us despite our worst selves.