Young Providence antiquarian Charles Dexter Ward discovers his ancestor Joseph Curwen was a colonial necromancer, and becomes consumed by research into his secrets. As Ward grows increasingly alien, Dr. Marinus Willett realises Curwen himself has been resurrected through the "essential salts" of the dead.
Lovecraft's only novel-length work blends meticulous historical atmosphere with full Mythos cosmology. The horror of distilling identity from physical remains gives the book an unusual psychological depth.