In fall 1916, Americans debate whether to enter the European war. "Preparedness parades" march and headlines report German spies. But in an isolated community in the Adirondacks, the danger is barely felt. At Tamarack Lake the focus is on the sick. Wealthy tubercular patients live in private cure cottages; charity patients, mainly immigrants, fill the large public sanatorium. For all, time stands still. An enterprising patient initiates a weekly discussion group. When his well-meaning efforts lead instead to a tragic accident and a terrible betrayal, the war comes home, bringing with it a surge of anti-immigrant prejudice and vigilante sentiment.