I’VE picked the yellow lane. The one with the grumpy processing officer who looks like she’s sucking lemons. I’ve not got a passport. Just my name – only, due to a mix-up with tickets, the name I must give is not my name. I give the name I must give to get through. My yellow-lane officer barks the question. In the booth next door, the blue-lane processing officer asks it kindly, a softness to her tone.

I’m in the presence of threat, anger.

My loves flash before my eyes. I’m quiet, turning over the answer to the question I’ve been asked: “What is the most important thing in your life?”

I want to say “family”. But think they’ll ask me to choose one. From years of being in the “immersive real-life experience of the UK Home Office processing” my senses are acutely attuned.

“Sion will only go with his mum,” I think. “My partner will choose our daughter. Sienna will only come with me.” The answer, terrible as it is, settles. “My granddaughter,” I say, the miracle of her soft skin against my remembering skin.

“The use of mobile phones is strictly prohibited in the Muster Station. Put your phone in the pouch and sit down.” I’m jolted away from the tugging memory of holding my three-and-half-year-old granddaughter, as she cuddles into me drinking her milk, and into the familiar stance of waiting to depart. It’s the tense stance adopted in every airport or waiting room. We know how we must be. We have been disciplined into these shapes by so many barking voices; loudspeaker announcements; intrusions of bells and monitors. I am given a purple paper fan.

Muster Station is the Edinburgh International Festival’s commission of Grid Iron Theatre Company. Back in 2006, Grid Iron, a site-specific production company, worked with the newly formed National Theatre of Scotland to make a production – Roam – at Edinburgh Airport. I was lucky enough to experience their work and every time I have been in Edinburgh airport since, that work has haunted me with its terror and its tenderness.

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The company’s work is ground-breaking, some of the best performance work I’ve ever witnessed as a scholar of theatrical work, which is situated on edges and in unusual intercultural situations with those seeking refuge.

Set in the future present, the central “character” of Muster Station is The WAVE, which is due in 6 days … 39 minutes … and 7, 6, 5.

The ticking clock is like water torture. Is water torture. We can all hear it. In a production which begins and ends in the large sports hall of Leith Academy, we are being processed, by the actors who are ourselves, to join – or not to join – the Arcs, built in Leith Docks, offering possible safe passage for those who are trying to escape The WAVE, to claim asylum in Finland. Yes, Finland.

In between the two “scenes” in the sports hall, we are mustered and moved by Guardians, into the school library, the gym, the pool and the common room, where four playwrights have been commissioned to ask the tough question of performers and audience participants alike: what, in the face of apocalypse – and the end of all you know, love and hold dear – does it mean to be human?

How would you be? Would you be like this – the woman in psychological meltdown screaming for her daughter Shona? Or like this – the man who speaks his mother language, who was refused asylum once before but opens his copious baggage, none of which he can take with him, and shares his food? Would you be like the Finnish immigration officer who makes you take an absurd asylum test and write out your own asylum claim? The futility of it matching word for word the utter futility of the Home Office’s own processing.

The reality of who will be granted asylum in this scenario has utterly replaced the idea that to seek asylum is a human right extended to all.

Or are you like the young people, full of their own sensuality, skipping between the pool holiday in Malaga and the steep cliffs of the waves in the dingy that capsizes; the helicopter pilot that asks them to choose who will be winched to Finnish safety.

In Finland they will have a lifetime of learning “the world’s most difficult language”, the immigration officer, a refugee herself, proudly announces to those of us already failing all the tests put to us. Are you like the revolutionary squaddie and the non-violent activist young woman, both finely balanced in a stand-off which is profoundly, absurdly democratic, clinging on to the hope that we will find a way out … “We will … we will … there is a plan … “Look at Arbroath.”

Arbroath? “Have you been to Arbroath?” was another question barked by the processing officers as we arrived, which flickers across our consciousness when it recurs, like a piece in a detective puzzle. In the school gym it becomes clear why the question was asked, that Arbroath too stands for hope, but without any clear idea of what that hope might be for.

And so it is that we encounter fragments of questions and answers to strange happenings for which we seek meaning and in which are held the seeds of the answers to the question what does it mean to be human? And who am I, for this dreadful but near certain future upon which we are still madly embarked?

The production announces itself as an “immersive experience” but like Roam before it I am already experiencing it as life-changing. The word “transformational” has become a little too glib but it is merited here.

When, for instance, I realise the utter futility of the exercise in making my own asylum claim, given that I already fail the basic criteria on income, I let the words from the experience thus far be those I write, folding in the lyricism of the performance of the Finnish woman remembering her grandmother’s wild honey:

I am remembering I am a crocodile.

Because all the bees died.

I am remembering I am a crocodile.

Because Suomi is a beautiful word.

I am remembering I am a crocodile.

I like honey and playing air guitar and staring at people.

No longer great but grateful.

Because the ocean exhales.

Such lyrical absurdism seems to be what Muster Station is drawing from me, on this apocalyptic threshold.

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We are makers of sanctuary and makers of war invited to live in the asylum seeking present of climate apocalypse which is indeed happening.

Our “white skins no longer work in the suns of 40 degrees in Fife”, and we know the truth of this in the summer of 2022. We are already glimpsing this present hurtling towards us.

We are clumsy and often ill practiced in our attempts at peace with others but when we remember there are no Others then there is a tenderness the best in us can perhaps grow towards, like plants to light. Maybe that’s the maturity spoken of in the dialogue between the professional woman in sheer panic and the asylum seeker she had formerly refused. “Strip back the cladding around us, no more role playing, it’s just you and me, remember.”

Something happened at the end which recalls the beautiful and moving real drama experiment undertaken by Amnesty International in Berlin after the arrival of one million Syrian refugees into Germany. As a set of head, hand and heart gestures brought the words of the Finnish immigration officer back to us – staring at people … beautiful faces … and I risked myself in the long eye contact with the actor-squaddie, the figure whose presence had most disturbed me with its latent violence, and most amused me with his eager banter and wit.

So it was that I returned his gestures of greeting. I could do no other because this is what saves our humanity, if not our lives, this fleeting space in between. A touch from another’s fingertip less than a second long, a gesture of comfort, of in-it-togetherness, of tenderness, that says there is no Other, we just are. A gesture of gratitude for another witnessing such a moment.

May we should stop being Great Britain, and start being grateful.

Gratitude. What is the most important thing in your life?

Thank you, Grid Iron.

And for the honey.

Muster Station is at Leith Academy at the Edinburgh International Festival, performed by Grid Iron Theatre, directed by Ben Harrison with playwriting by Nicola McCartney, Uma Nada-Rajah, Tawona Sitholé and Ben Harrison

Alison Phipps is Unesco Chair for Refugee Integration through Languages and the Arts at the University of Glasgow