I’VE never thought too much on the type of things that get said during confession, but hearing a priest respond to an imminent death threat with the brisk riposte ‘that’s a startling opening line’ is an intriuging start to what, in the most part, is a brilliant black comedy.

Writer-director John Michael McDonagh’s Calvary casts the imperious Brendan Gleeson as Father James, a (mainly) gentle, brooding representative of the Catholic church striving to guide a morally bankrupt Irish seaside town (Sligo) away from seemingly inevitable self-destruction.

His imminent doom is intimated in the shadowy confines of the confession box.

The parishioner, a mystery agent of malcontent who reveals serious abuse at the hands of clerics from the age of seven, tells James he will murder him in seven days.

The Father has been picked for being a ‘good man’, the idea being a dead priest of the innocent variety makes something of a starker point than righteous vengeance against a paedophile, as if disassociation from the church is that important given its fall from grace.

Ostensibly this is a whodunnit, or perhaps more appropriately, a who-will-do-it, as the murder is pencilled in, in a week’s time, on Sunday, on the beach.

The whodunnit element feels a bit like childhood game wink murder, because Father James says he knows who wants to kill him, but, due to the sanctity of confession, and his own faith, carries on with the charade anyway.

Potential assassins surface like teenage girls at a Gary Barlow concert armed with motives from jealousy to self-loathing.

Brendan (Pat Short), a pub landlord, has the hostility of an ice berg, partly buried, but never far away.

Doctor Fran Harte (Aiden Gillen) believes in neither religion nor bedside manner, teasing James with both, while Veronica (Orla O'Rourke) prefers any bed other than her marital one.

Dylan Moran’s Fitzgerald, a retired banker rich of self-hate dangles money to the church in mockery of it as a path to forgiveness, and Jack (Chris O'Dowd) is a bumbling butcher with a sinister undertone.

The common denominator of all is an attitude towards the church, and so James, that labels it as a fallen symbol neither worthy of recognition or respect.

He is taunted, teased and dismissed maliciously.

In answer, is the faith of James, partly hidden by an innate sadness, but also palpable anger.

Gleeson’s performance is terrific, in resigning himself to tending to the impossible flock, with a kind of tender stoicism.

When making the point people of faith generally have it ‘from fear of dying’, James reveals the key interrogation of the narrative: what is faith, and how does one prove it?

He does so by walking willingly to meet his fate, in belief it may yet be different, but prepared to face it, if it is not.