You never know where an idea for a book will come from. Furthermore, you never know when you’ll be ready to write it. My latest novel, SUMMER FRIDAYS, was inspired by a moment I once witnessed over two decades ago in New York City. It happened in October of 2001, when I was riding the subway in Manhattan. Less than a month earlier, the city had been rocked by the terrorist attacks of 9/11, and New York was very much reeling with a devastating mixture of shock and grief. I suppose in general this was always going to be a memorable time to be living in New York – everybody in the city, if not everybody on the planet, felt the historical weight of what had just happened in September when the towers came crashing down. And yet, the memory that sparked my eventual novel was actually rather simple in nature: It involved a mysterious interaction between two people. In the weeks that followed 9/11, people in New York were still putting up missing posters, still looking for loved ones whose fate had not been confirmed. I remember I was riding the train that day, staring at a missing flier…