When I first saw the Irish playwright Martin McDonagh’s Lieutenant of Inishmore on stage in New York in 2006, I never imagined that this brilliant, sharp, funny, melodic, verbose writer would make the jump into cinema. His work seemed made for the stage, with characters and patterns speaking beautiful, articulate sentences more suited for theater than cinema.

Imagine my surprise then, on him winning the Best Screenplay award this year at the Oscars for the spine-chillingly poignant, belly achingly funny film which he also directed, Three Billboards Outside Ebbing, Missouri – a heartbreaking film about a woman who goes all out to find her daughter’s rapist and killer.

Mildred Hayes (played in a feral, funny, riveting, unforgettable performance by Frances McDormand who won the Best Actress Oscar for her role) is infuriated by the lack of progress from the town police in the brutal murder of her teenage daughter Angela. Separated from her drunken abusive husband and consumed by grief at the loss of her daughter, Mildred puts down a payment of $5000 to paint an accusing series of signs on three billboards just outside the town – shaming the town police who have no leads even months after the killing. Needless to say, the small insular town is aghast at her brazen, unrepentant attitude on accusing one of the town’s most beloved members, Chief Willoughby (Woody Harrelson) of ineptitude. It also doesn’t help that Chief Willoughby is dying of cancer.

The film follows a tight, sharp dramatic arc that includes unforgettable performances from a cast of actors who play the town’s kooky characters in a story about how revenge can consume, and forgiveness can redeem.

Sam Rockwell, another under the radar but incredibly fine actor won for Best Supporting Actor playing Officer Jason Dixon- a bigoted policeman whose life is changed by Mildred’s vendetta.

McDonagh does the almost impossible, which is to create a deep, dark film about violence, loss, racism, brutality and sexism, lacing it with irreverent humour and a complete, compassionate understanding of the flaws of humanity. McDonagh understands that “No man is as bad as his worst act” – but nevertheless everyone must pay for their actions if they have morals: for the immoral sociopaths, there is no reprieve.

All of McDonagh’s films, including the hilariously funny and incredibly bleak In Bruges (2008), are suited almost more for theater than for cinema. Yet this film manages to be a powerful work onscreen: it creates a sense of place so strong that one believes McDonagh’s version of Bruges and quiet Ebbing, Missouri are out there somewhere.

While Three Billboards Outside Ebbing, Missouri lost in the Best Picture category to The Shape of Water, it is as worthy a contender, if not more deserving. For those who want to see a real masterpiece this year, this is the film to watch. Do not miss this film, it is the stuff of legend.