The man Patricia Lane loves is gentle, intelligent, and sensitive. Yet somewhere within Nicholas Devine lurks another presence-cold, cruel, and terrifyingly unlike the man she knows.
At first, Nicholas's strange transformations seem impossible to explain. His expression changes, his voice becomes harsh, and a disturbing personality emerges with desires and impulses entirely foreign to his ordinary nature. Frightened by what she has witnessed but unwilling to abandon him, Patricia turns to psychologist Dr. Carl Horker. What begins as an investigation into the mysteries of the human mind soon descends into something far more dangerous as Nicholas's darker self grows increasingly powerful.
Is Nicholas suffering from a divided mind, or does something more sinister exist within him? As psychology, medicine, fear, and seemingly supernatural evil collide, Patricia and Dr. Horker are drawn toward a revelation stranger than either could have imagined. Blending psychological horror, speculative science, romance, and suspense, Stanley G. Weinbaum's The Dark Other explores the terrifying possibility that the greatest monster a person can encounter may be hidden within the human mind itself.