Introverted backpacker Jeremy wanders off trail and discovers an eccentric, otherworldly town nestled in a mountain basin. The people he finds there are pleasant, but a little bit peculiar. He befriends a reticent doctor and his wife, who is struggling with dementia, and Margery, who regularly leaps from a cliff in death-defying bungee jumps. Why, he wonders, do the otherwise healthy and upbeat townspeople seem to be disappearing?