American countryside, 1950. The Warlock begins with a little boy on a train, seated across the aisle from his mother and baby sister. The boy entertains himself by telling stories about a warlock he saw out the window. But his mother doesn’t encourage such flights of fancy; she is absorbed in her reading and won’t indulge her son’s imagination.
A stranger soon joins them in the carriage, a seemingly innocuous elderly man. There is a genial exchange between the boy and the man, as the latter asks what the youngster has been watching out the train window, then even encourages his make-believe. The mother, who was initially anxious when the stranger arrived, returns to her reading.
The elderly man proceeds to sit down next to the boy and reveal that he once had a sister, too—who may have been a witch. He adds that he . . . choked his sister to death, cut off her head, and dismembered the body. The mother is naturally shocked at such an admission (or fantastication) and threatens to call the conductor, so the stranger discreetly departs. The woman gives her son a lollipop and tells him that the old fellow was just teasing—in response to which the boy says only, “Prob’ly.”