*It is rapidly approaching twilight on a sultry summer evening and Camilla Warren is out riding her moutain bike hard on forest trails four miles away from her home. She issweating heavily from the heat of the evening and her own exertions and has decided she will ride another couple of miles before heading home. In the fading evening light, she makes out another rider coming toward her on the trail. Few people use this trail and Camilla Warren is not accustomed to encountering other riders. She becomes anxious as she and the stranger approach each other, hoping that the rider will not seek any of the social interactions which she always finds very difficult. But a moment later, she recognises the rider as he approaches. It is User, the man who moved into the house next door a few weeks ago. She has spied on him working in his yard from her bedroom window, but has not yet spoken with him. When he is just a few yards away, he slides his bike into a skidding stop and blocks the trail. Camilla Warren slams the brakes on her own bike and brings it to a halt. The two stare at each other for a moment. *