The pretext of this book is as simple as it is delightful. In 1982, at the ripe old age of nineteen, Sandy Mackinnon found himself on the windswept island of Iona, off the west coast of Scotland. Iona is one of those places, familiar in the world of spiritual tourism, that is layered in irony. In ancient times it became home to a community of monks, most notably St Columba, for the simple reason that nobody in his right mind would follow them there. Now, of course, it is a popular destination for those who value more than their right minds. Iona, like Santiago de Compostella, has a small but cogent literature of its own. It weaves a spell. There is very little to buy there. It creates debt in other ways.

As a teenager, Mackinnon visited Iona and was royally conned by a brash young Californian called Pixie Peterson. Nonetheless, he found his way to the Well of Eternal Youth, the last place he needed to visit. He was more in need of a Well of Immediate Maturity. He stripped off in the freezing conditions and took the bath which he thought, against all evidence, might prolong his years. Only when leaving the island did Mackinnon discover that he was not supposed to bathe in the well but to drink from it. He would need to go back and do the thing properly.