When Griffin is in Iping in Chapter 3, he is bitten by a dog. Before the invention of the rabies vaccine in 1919, dog bites were feared because of the deadliness of the disease. Rabies is a virus that results in madness, an inability to drink water, and eventually death. The rate of fatality is nearly 100% and, before mass pet vaccination efforts, the virus was most commonly spread by dog bites. For this reason, when the people of Iping react to Griffin’s bite, they assume the worst.
Since there was no apparent reason for the dog’s aggression toward Griffin, it makes sense that they would assume the dog was rabid. Mr. Huxter suggests out of concern: “He ought to have it cauterised at once [...] especially if it’s at all inflamed.” A woman of Iping says, "I’d shoot en, that’s what I’d do." Mr. Huxter urgently insists on cauterization out of fear, while the woman jump straight to murder—and it's unclear whether she's referring to the dog or to Griffin.
The bite foreshadows the end of the Invisible Man, for Griffin’s fate is similar to the symptoms of those with rabies. Due to a madness that springs from his desire for power, he enacts a spree of ultra-violent behavior, is prevented from receiving food and drink, and then dies in agony.
In Chapter 2, Mrs. Hall has a dream that foreshadows Griffin’s rampage:
She was all the more inclined to snap at Hall because the stranger was undoubtedly an unusually strange sort of stranger, and she was by no means assured about him in her own mind. In the middle of the night she woke up dreaming of huge white heads like turnips, that came trailing after her, at the end of interminable necks, and with vast black eyes. But being a sensible woman, she subdued her terrors and turned over and went to sleep again.
Dreams are often a medium of prophecy or foresight in literature. In addition, dreams often are read as indications of one’s irrational hunches and subconscious anxieties. Mrs. Hall has a hunch that something is off about the stranger, and this suspicion manifests itself in her dream. Symbols of Griffin's disguise—large turnip heads—run after her. The turnips are monster-like apparitions in the dream. And surely enough, Griffin later behaves like a monster. He chases innocent victims around and threatens bodily harm. His behavior is similar to how the black-eyed turnip heads terrorize Mrs. Hall in her dream.
Hall dismisses her dream because she is “sensible” and thereby ignores her general discomfort around Griffin. Sensibility, throughout the novel, allows Griffin to get away with a lot. Many individuals (like Doctor Kemp initially) don't believe in the Invisible Man because the tales sound impossible, which thereby allows Griffin to go around causing mayhem relatively easily.
In Chapter 4, residents of Iping, Mr. Teddy Henfrey and Mr. Gould, suspect that Griffin is up to no good:
Elaborated in the imagination of Mr. Gould, the probationary assistant in the National School, this theory took the form that the stranger was an Anarchist in disguise, preparing explosives, and he resolved to undertake such detective operations as his time permitted.
The suspicion is likely motivated by two factors: that the stranger is an outsider and that the stranger has a very odd appearance. Neither of these factors, under normal conditions, would be a good guarantee that the stranger will go on to make trouble. In fact, assuming that a random stranger is a terrorist is normally irrational behavior.
However, Mr. Henfrey and Mr. Gould are right to be suspicious of Griffin. Griffin does end up being an anarchist in a certain sense. Although he shows no familiarity with or allegiance to the actual political philosophy of anarchism, the Invisible Man frequently disobeys legal codes and does not believe laws have any moral force over him. Also in a certain sense, he blows up the town in a terroristic manner. He sows social disorder in an attempt to assert his own power, trying to rule the English countryside with a "reign of Terror."
In Chapter 24, Griffin reveals his goal to Mr. Kemp. He wants to impose a Reign of Terror:
Not wanton killing, but a judicious slaying. The point is, they know there is an Invisible Man—as well as we know there is an Invisible Man. And that Invisible Man, Kemp, must now establish a Reign of Terror. Yes; no doubt it’s startling. But I mean it. A Reign of Terror. He must take some town like your Burdock and terrify and dominate it. He must issue his orders. He can do that in a thousand ways—scraps of paper thrust under doors would suffice. And all who disobey his orders he must kill, and kill all who would defend them.
The Reign of Terror is an allusion to a period in the French Revolution. The French Revolution was initially a revolution driven by democratic principles against an unjust monarchy. However, one of the leaders of the French Revolution, Robespierre, took power after the French Revolution’s initial success.
The revolutionaries disposed of the monarchy, but Robespierre was scared about resistance to the French revolutionary ideals, so he became somewhat dictatorial and instituted a completely new calendar, strict laws, and public executions. Later, Robespierre himself was executed when other revolutionaries became dissatisfied with his rule.
Wells uses this allusion to show the degeneration of Griffin. Like Robespierre, Griffin started out with somewhat positive—or at least neutral—intentions: he wanted to engage in scientific discovery. However, when he felt threatened by other people and gained the power to exert his will, he turned to more brutal methods. Griffin wants complete control of the English countryside so that he can rule like a monarch.
The Reign of Terror allusion foreshadows that Griffin will eventually be rejected and killed by the people he attempted to rule—just like Robespierre. In this regard, the events of The Invisible Man warn against the desire for power at the expense of others.
At the end of Chapter 26, after Griffin has successfully evaded the men hunting him, Wells directly foreshadows Griffin’s downfall:
In the night, he must have eaten and slept; for in the morning he was himself again, active, powerful, angry, and malignant, prepared for his last great struggle against the world.
The ending is told directly to the reader: the following struggle will be Griffin's downfall. There is no ambiguity regarding whether Griffin will be victorious or fail. Although this takes away the mystery from the scene, it adds suspense surrounding Griffin's demise. The characterization shows the manner in which he greets his death, which is like the manner in which he lived: angry and malignant.
Griffin's rampage is malignant indeed. In the chapter after the foreshadowing appears, Griffin murders Colonel Adye and ruthlessly pursues Doctor Kemp out of rage. This passage emphasizes that being greedy and self-interested (or otherwise immoral) leads to one's downfall. Griffin has no chance for redemption, he already lost any possibility of rehabilitation when he refused Doctor Kemp's offer to help him publicize his findings. Now, as signified through the foreshadowing, his fate is sealed. The direct foreshadowing implies there is no other possible end for The Invisible Man.
Griffin, because he led an immoral life, will meet an end fitting for his crimes. Although he evaded punishment through the night, the end of Chapter 26 promises that the next day is his last great struggle—in doing so, the narrative indicates that he finally will meet justice, or at least some sort of retribution, for his crimes.
