August Chalmin is a tall, pale, painfully shy young man with blood-orange hair and sun-shy eyes, who hides his awkwardness working behind the counter of the gourmet deli in London's Shepherd's Bush neighborhood. One winter day he finds a rash on his arm that resembles the crystalline frost on his windowpane. Later, snow begins to fall around his head and his fingers turn blue. Is it some rare disease that has triggered this strange reaction, or the...