Every now and again, a book comes along that catches you out. You think you know where it's leading to, but when you get there, you are still taken aback. A calypso is a West Indian folk song which is made up as the singer goes along. In this story set within a leprosarium on a Caribbean island, the calypso is that of a troubled orphan boy, who has been placed in the care of the island's doctor. I emerged from this book feeling as though I had woken from a bad dream: shaken, sweating and exhausted. This story will stay with me for a long time.