内容简介：
It is at a party that Richard Hedon first hears about the mysterious Paul Clyro. Clyro had been a scientist, doing secret work on viruses with a colleague named Wolsingham. But Wolsingham had committed suicide and Paul Clyro found the body, walked out of his house and vanished without trace. Richard follows Clyro's trail - all the way to Madeira, where a man known as Gavin Chilmark is living a comfortable and contented life, free from any breath of suspicion. . .