It's 1923 and Pádraic Súilleabháin (COLIN FARRELL) is a single man who lives with his sister, Siobhan Súilleabháin (KERRY CONDON), on the small island of Inisherin off the coast of Ireland. Pádraic is a pleasant, unassuming man who enjoys the company of his pet miniature donkey and local songwriter and violin player Colm Doherty (BRENDAN GLEESON).

That is, until Colm suddenly decides he no longer wants to be friends with Pádraic, a development that befuddles the latter and confuses the likes of young adult Dominic Kearney (BARRY KEOGHAN) who lives with his abusive father, Peadar (GARY LYDON), the local cop.

As Pádraic tries to get to the bottom of Colm's abrupt termination of their friendship - that includes going to extreme ends to make sure Pádraic understands his ultimatum -- it's unclear how things will play out, especially as an older seer, Mrs. McCormick (SHEILA FLITTON), predicts tragedy will strike the island.

Friendships can be a funny thing. Those forged in childhood either remain strong throughout the participants' lives, or they begin to wane and eventually evaporate once those friends start drifting in different directions in the teen or later adult years. And then some can go months or even years without a trace of contact in that time yet somehow miraculously revive once the parties are reunited for whatever reason.

Rarest among the friendship parameters are those where one person suddenly decides -- seemingly out of the blue and certainly coming as a shock to the other -- that they no longer want anything to do with their "friend." I can certainly see that if the person being dumped, so to speak, has done something particularly heinous, and I can sort of understand if they've turned out to be a full-on kook who's suddenly come out of the closet wearing their conspiracy-minded freak flag with pride.

The question of what's caused one friend to unfriend another is the driving force behind "The Banshees of Inisherin." In this latest offering from writer/director Martin McDonagh ("Three Billboards Outside Ebbing, Missouri'') -- that reunites its two stars from an early movie made by him ("In Bruges") -- Colm Doherty (Brendan Gleeson) has, seemingly out of the blue, abruptly decided he wants absolutely nothing to do with his lifelong friend, Pádraic Súilleabháin (Colin Farrell).

The year is 1923 and the two live on the fictional titular island just off the coast of mainland Ireland where the Irish Civil War rages on and can occasionally be heard from a distance. A songwriter, Colm lives alone, while Pádraic lives with his sister, Siobhán (Kerry Condon), and a small menagerie of animals, many of which Pádraic likes to let into their small house.

The two men routinely get together for a pint -- or two or three -- but now Colm has declared he wants nothing to do with his now-former drinking buddy, something that perplexes Pádraic, his sister, and young adult Dominic Kearney (Barry Keoghan) whose abusive father is the local constable.

Pádraic wants to know if he's done something wrong -- perhaps drunkenly -- but Colm says his mind is made up and the matter is settled. When Pádraic won't accept that, Colm threatens to cut off one of his own fingers each time Pádraic directly addresses him. And cue the remainder of the quirky black comedy that then segues into something far darker, disturbing, and ultimately depressing.

It does take a while to get there, and you wonder in the process where McDonagh is going with the material and whether it's going to end up being too repetitive and thus simplistic as Pádraic tries to solve the unfriending. Once he accepts that and decides to get even, that's when things take a turn and most of the fun goes out the window as the filmmaker explores masculine relationships, the notion of friendship, and the sense of losing an opportunity to last -- at least through art -- beyond one's time on this third rock.

It certainly won't be for all viewers -- heck, even most -- as things unfold. But there's no denying it's a mesmerizing tale told well, with excellent performances all around. Expect lots of award love to come this film's way once that season begins. Notwithstanding that, if anything "The Banshees of Inisherin" is likely unlike anything else you'll see this year at the movies. It rates as a 7 out of 10.