Some years ago, I was invited to meet at six in the morning on a hot summer day in Rome to watch while an archaeological team from the American Academy in Rome re-opened an excavation in the Roman Forum on the Palatine Hill. The first chapter came to me in this way, watching the team at work moving rocks, sifting the findings, while at the same moment imagining a catastrophic release of a deadly virus killing two of the archaeologists. In this “imagining” I polished off the head of the American Academy team whom I had known for years. I told him about his fate later, which he laughed about good naturedly. With this, the story was off and running. I had no idea exactly where the story was going but I knew the characters would help me find the way. And they did.