We live in a Peter Pan culture, where everyone wants to stay young forever. Ursula Martinez is afraid of growing old. She has no pension, no partner and no children, and she doesn't want to become one of those old ladies who smear lipstick crazily around their mouths.
In OAP, Martinez gets us to confront those fears and prejudices, makes us play bingo and invites us to kiss the geriatric. It is the juxtaposition of all these things that makes the show such a crazy enchantment, along with a film of a pack of pensioners from Morecambe who cackle like a Greek chorus and show the young fool Martinez the error of her ways.
The show is a contrivance, of course, and it is not without self-indulgence. But it is also fresh and different. In its final moments, as it makes us embrace our fears, it feels like a show that is not only warm and witty but also makes a difference.
· Until August 28. Box office: 0131-226 2428.