Stanley has a swagger about him, when first we peek into his home. He’s preening in the mirror, slicking back his hair, a little other-worldly but seemingly self-assured. The calendar on the wall says it’s 1950 – and Stanley’s keen to tell us about a new show called The Archers he’s just heard on the radio. But Stanley’s noticed something else in the mirror today… and as we re-visit him over the course of the following 20 years, we witness a slow decline into illness and isolation.

Writer and performer Conor Clarke McGrath treads a fine line as Stanley, and by and large he succeeds. On the one hand he’s likeable, if a little distant; he’s physically expressive, engaging to watch, and vulnerable enough to warm to. On the other hand, it’s clear he’d be a nightmare friend or neighbour, complaining about trivial disturbances and refusing to be sociable because he’s already having “enough fun”. You sense that something’s not right here, but it’s only when he reacts with abject horror to a simple ringing phone that we start to understand just how serious it could be.

And as we re-visit Stanley ten and twenty years later those fears are confirmed. McGrath expresses the reality of Stanley’s life through subtle, telling details: his strange obsession with tea-making, the way he clenches his toes under him as though he’s trying to hang onto the world. As the years flick by in well-planned audio montages, we hear how much the world is changing outside Stanley’s home – but, conversely, see how little alters inside.

For maybe the first two-thirds of the play, it’s not clear where this is going. It’s obvious that Stanley is somehow damaged, but he seems happy enough in his self-constructed bubble, and he doesn’t win much sympathy with his increasingly-irascible interactions with the world outside. But the hints of something darker are beginning to mount and, as the calendar moves on to 1970, the dam-wall breaks. At last we learn what’s truly inside Stanley’s head, and how even his place of mental refuge has become a charred and battle-scarred wasteland.

And suddenly I got the point. The first scenes try your patience, because Stanley would try your patience. The physical sequences are kooky and awkward, because Stanley would seem kooky and awkward until you got to know him. The story comes out frustratingly slowly, because it takes Stanley decades to sort it out in his own brain. But if you stick with Stanley, you’ll come to understand him – and the connection you’ll feel then is a powerful reward.

There’s a price to be paid for such sincerity, and there’s a lot McGrath could do to make Stanley a more approachable, more instantly-appealing piece. But I hope he won’t. Like a real-life friend in need, it demands your effort and sometimes your patience, but you’ll know in the end it was all worthwhile. And it doesn’t hurt to remind us that – in the world outside the Fringe – cries for help don’t come in neat and simple packages.