Edward Sayers arrives in a small town and is greeted by Amanda Strickland. Edward has been sent by the government in order to investigate a strange insanity that seems to be spreading from person to person.
First, he visits Amanda's father to see the mysterious insanity firsthand. Amanda's father is hopeless insane and rambles about his dead wife. Fortunately, he offers a clue. He describes his morning and after he says he was paid a visit by an elderly Mrs. Hotchkiss he stars screaming. Edward and Amanda head to Mrs. Hotchkiss's house. Mrs. Hotchkiss seems to be a normal old woman until she tries to stab Edward with a knife. Edward manages to subdue the old woman before she does any harm.
Later, in the lab, Edward is unable to discover the cause of the insanity. He finds nothing in the air or water. Amanda, however, figures out that the insanity is like a disease. It spreads from person to person like a cold. In the hospital, Edward and Amanda are disturbed to discover that there is nothing physically wrong with any of the victims of the insanity. As Edward tries to organize a quarantine, Amanda discovers that insanity seems to have started with one man: Andrew Potts. Since Andrew Potts is in the hospital, Edward goes off to see Potts's brother, Jeffrey, a professor of Far Eastern Studies.
Edward goes to Jeffrey Potts's house and finds that he too is in the grip of insanity. Potts tells him that he went to study in the Orient and discovered the meaning of "Everything." Potts tries to tell Edward the Meaning, but Edward manages to stay away from him. Potts then reveals that he intends to reveal the Meaning to everyone over the radio. Potts manages to knock Edward out and heads off out the door. Edward comes to and heads to his jeep. He listens to the radio as Potts prepares for his big statement. Just as Potts is about to reveal the Meaning, Edwards gets to Amanda's house. He runs inside and manages to shut off Amanda's radio. Edward insists that they leave, but he then sees that one of Amanda's neighbors has already arrived ahead of him. Amanda whispers into his ear and he screams.