A pathologist, Dr. Warren Chapin (played by Vincent Price), discovers that the tingling of the spine in states of extreme fear is due to the growth of a tingler—a spinal parasite which can kill the host unless it is destroyed by screaming.
The lives of six girls belong to different worlds although connected to each other through a doll called Molly, whose existence dates back to 1976, when she appeared among the rubble of the great fire of the San Carlos orphanage, in northern Spain.