A choir sings Hen Wlad Fy Nhadau as the usher closes the door. A man in a rugby shirt – the old type, warm and baggy – is waiting on the stage. It couldn’t be more Welsh, the heart of the Valleys, sometime in the sixties maybe. But the rugby pitch, we hear, is “still a right mess”; the village shop’s only just opened again. There’s something unspoken hanging in the air. You might already have guessed where we are.

It’s a full twelve minutes before they mention the name, but of course, this is Aberfan. In 1966, a poorly-maintained colliery tip collapsed onto the town, killing 109 children in their junior school and 35 people elsewhere. The scale of the tragedy feels impossible to comprehend, and Mr Jones wisely picks a narrower field of view: the rugby player Stephen, his childhood sweetheart Angharad, and the younger brother Dafydd, whom the two of them helped raise.

Playwright Liam Holmes, who also plays Stephen with measured intensity, sets the focus very much on everyday life. Before disaster strikes, he paints a picture of a small and self-reliant town: a place where everyone’s known everyone for all of their lives, and even Cardiff or Swansea seem somehow far away. We learn of Stephen and Angharad’s complex connection, a relationship that’s gut-wrenchingly tested by their differing responses to the tragedy shortly to come. And Dafydd, never seen on stage, is a vibrant figure nonetheless, a little boy who simply likes to play.

We know, of course, how Dafydd’s story is likely to end – though there’s a glimmer of defiant hope he might somehow make it through. We know, too, how significant it will become that Angharad is a nurse. When the moment inevitably comes, we witness her step up to the crisis… but as actor Mabli Gwynne skilfully reveals, her practical demeanour conceals a profound sense of trauma and loss.

While the script very intentionally reflects the sweep of normal life, the more gossipy chunks of dialogue might warrant an edit – it’s hard to focus when we hear about so many people who may or may not be important to the plot. On the whole, though, this is a play which sets out with a sense of purpose, and discharges its mission well. It hints at the controversies and the deflection of the blame that have come to define Aberfan, but it reminds us that – in the short term at least – nothing mattered more than to find a path forward, through the ruin of everyday lives.