“No man is an island, entire of itself; every man is a piece of the continent, a part of the main.”

These are the words written by 17th century English poet John Dunne, words that still resonate today. But not with writer and director Martin McDonagh, who uses the theme of isolation figuratively and literally, throughout his latest film set on an island, off of a bigger island, off of an even bigger island.

1923, and living on Inisherin, a small island off of the coast of Ireland, is Pádraic (Colin Farrell). He lives with his sister Siobhán (Kerry Condon), along with some livestock, including a miniature donkey called Jenny, who he’s rather fond of.

Someone else he’s fond of is his best friend Colm (Brendan Gleeson), who he meets up with religiously every day at the local pub for a chat over a pint or two.

That was the case however, until one day Colm informed Pádraic that he no longer wanted to go to the pub and spend time with him, because he realised he no longer wanted to be friends.

At first Pádraic put this down to him just saying something he shouldn’t to Colm whilst being drunk, but after a few days he realises that Colm is indeed very serious. So what do you do when your best friend tells you he doesn’t want to be friends anymore?

For his follow up to his hugely successful, Oscar-winning Three Billboards Outside Ebbing, Missouri, McDonagh re-unites Farrell and Gleeson from his first feature, 2008’s In Bruges, for a very different film.

Whereas the theme of lost love is one that many films thrive on, McDonagh changes the focus somewhat to that of lost friendship. It is a film about self-reflection, as well as what it exactly means to have friends; what is their purpose and could our lives actually be better without some of them?

Of course while his character Colm is grappling with this concept, he doesn’t fully realise the repercussions of his actions, and how their affecting his now ex best friend, who is clearly struggling.

It’s a tome to the fragile nature of masculinity, as well as the often unseen weighty responsibilities that can often come with a friendship.

His film, as intimate as it often feels, could easily be adapted to be a play, such is the beauty of the screenplay, but then it would lose out on a major factor – its locale. It’s almost trite these days to say that the fictional island of Inisherin is almost character in itself, but in this case its true. It’s a fairly bleak and remote place, that only intensifies the isolation that all the characters suffer from, in one way or another.

It’s also a meditative examination of mental well being too, especially in men. A number of characters who live there, not just Colm and Pádraic, are struggling with their own mental issues. The kind of issues that men especially are so good at sweeping under the carpet, often to the point where a severe incline road sign has to be placed in front of it, as the carpet rises sharply in front of them.

McDonagh’s script also has a Shakespearian quality about it, resembling the possible outcome of characters such as Guildenstern and Rosencrantz in their twilight years of retirement. And to call it a tragicomedy would be most accurate indeed.

It’s a film rich in performances, but in particular from Farrell, who shows Pádraic wearing his heart very much on his sleeve throughout, as he comes to terms with his best friend effectively telling him, it’s you not me.

Another striking turn comes from Barry Keoghan, who is just outstanding as the young Dominic, who is really simply seeking friendship of his own; he is up for one of the film’s many Oscar nominations, and no one deserves it more.

McDonagh is proving to be an exceptional talent, especially when you consider that this is only his fourth film.

The Banshees of Inisherin, much like the work of John Dunne, is poetic, with its incredible remote island backdrop and its beautiful use of language, as it depicts heartbreak in its various guises, with a profound sense of vulnerability and melancholy.

It is that rarest of gems, a film that is both funny and moving, making it a genuinely bittersweet experience.