In the dark days before the Civil War, a doctor stumbles across an unnatural secret Davis Bentwood has nearly finished medical school when he meets an abolitionist dwarf walking across Harvard Yard. Jeb Coffin is a nonpracticing doctor, a devoted student of transcendentalism whose home life has been shaken by tragedy. The two men become friends, and Coffin invites Bentwood to rural Maine to save his family from itself. The Coffins are noted abolitionists, their home a stop on the Underground Railroad, and lately they have been menaced by a supernatural terror. The tragedies are countless: two brothers killed, a father driven mad, and a baby frozen solid in its crib.   At first Bentwood cannot bring himself to acknowledge the impossible horrors that have cursed this family. But he will not survive his sojourn in Maine unless he can open his mind to the possibility that something evil is waiting in the dark.