The one-person show on the Festival Fringe is an admirable feat. To sustain a theatrical monologue, especially one that is (or appears to be) a personal narrative, requires good timing, firm structure, and enough tonal variation in order to hold the audience. It also needs slick technical back-up.

Killymuck has all of this from the start, launching in with our character, Niamh, splashing around on a box. Is she on a boat, or learning to swim? No: she is gushing at speed from her mother’s womb. That sets the pace for the whole narrative, as we whoosh through Niamh’s childhood, growing up on a seventies housing estate in Northern Ireland.

Sometimes things feel a little too quick-fire; there are lots of words to take in (though none are missed) and it feels as if we, the audience, need to take a breath. The tech are on top of it, and this slick storytelling only stops when Niamh takes to the microphone.

It wasn’t obvious in the first instance, when the mic was hand-held, that this was a piece of ‘commentary’ in the style of a Greek Chorus. But at the second occurrence when a mic-stand was used, with full lights, clearly this was the ‘preachy’ bit.

I don’t mean this in a derogatory way: all of my Fringe reviews this year are shows taken from the Amnesty International Freedom of Expression Awards longlist. You might expect the didactic, although due to the same vocal delivery I was left wondering whether this was Niamh’s story. Or was it her opinion?

Back into the narrative, we are ‘shown’ rather than ‘told’ of life on the estate, all with the simple aid of a single prop: a wooden box. We see all the stuff and dross of the benefits-class, and the associated spirals of poverty for those denied opportunity simply because they were born on a pauper’s grave – literally, in the case of Killymuck, so Niamh tells us. No wonder she thinks the place is cursed.

There are universal stories of the under-privileged (alcohol, abuse, abortion) yet of course they have a peculiar resonance in Northern Ireland, especially with a good (I mean, bad) dose of religion thrown in. Another key part of Niamh’s story is education, the importance of which is drummed into her by her bullying, drunken father.

Sadly, Niamh doesn’t quite share her older sister’s success. Despite this, she gets into university but (possibly following in her father’s footsteps) flunks out due to alcohol misuse. So how does it end? I’m not one for plot-spoiling. However, inevitably, there is a final ‘commentary’ which is on the writing process itself: which of three possible endings should she choose?

We are ‘shown’ (not ‘told’) a simplified version of Angue McGuire’s illustration of equity versus equality; Niamh’s single prop is now in the picture: standing on a box to achieve the same as your neighbour who happens to be taller, or two boxes if you are even shorter. Everyone deserves an equal chance, but some need a step up. This is what equity means. And this is what Niamh has been showing AND telling us all along. However, it is not ‘Niamh’s’ story at all.

Energetically and convincingly played by Aoife Lennon, this is a new play by Kat Woods, drawn from her own experience of being brought up among the ‘benefit classes’ – a social/economic grouping she feels is under-represented in theatre. This engaging piece is didactic, and rightly so: these people need a voice beyond the negativity of media stereotypes.

Killymuck, 18:25, Underbelly McEwan Hall, until August 27th (not 13th)