Dr. Gillespie is contacted by his old friend Emma Hope, headmistress of a prestigious girls school. She's concerned about Roy Todwell, the young man one of her girls, Marcia Bradburn, has been seeing. Todwell has shown serious bouts of violence over the most minor event and working with a colleague, Dr. Gerniede, Gillespie concludes that the young man is suffering from serious mental illness. He has little success in convincing Todwell's parents of the seriousness of it all - they prefer to take the opinion of their own physician who thinks psychiatry is just a lot of mumbo jumbo - and the young man's condition deteriorates. Todwell soon sets out for New York with only one goal in mind - to kill Dr. Gillespie.