Laura is in a care home. Her son visits her regularly; sometimes he calls. Laura has dementia, and to us the audience, her condition makes her seem older than she really is. But in her head, she doesn't feel elderly; through her hazy memories one stands out, from a long time ago, one summer and her interactions with Evelyn.

Thaw a very cleverly structured show. I've seen a reasonable variety of Fringe shows over the years, so I was pleasantly surprised by a setup that was new to me. The whole cast is on stage, with the relevant characters centre-stage for their scenes, and others on the sidelines. As we flick between the Laura of today and the one from the past, the scene switches are accompanied by the crackling white noise of a record player.

Laura’s memories cast her friend (and nearly her companion) Evelyn in a certain light. As with all stories involving an unreliable narrator, Thaw too adds an extra dimension to the plot. What did Evelyn really feel? How much of what happened has another side to it? And how do we embellish our memories from the past?

From a young cast come clear signs of great potential. Eilidh MacKinnon is particularly convincing as an older woman, vulnerable, but still full of spark and unrelenting in her arguments. The mother-son relationship is beautiful, and even in a short space of time the nuances of their bond are established.

A few things seem superfluous. If there is a metaphor in the scenes involving the chicken, then it is lost on me; and if there isn’t, then I’m not sure why they are included. Even so, I am impressed with the finesse and stage presence of what is very enjoyable theatre from Mermaids – The University of St Andrews Performing Arts Fund.