Doctor Kemp reads a strange letter accusing him of being “amazingly energetic and clever.” The letter-writer, Griffin, says that he ate and slept to “spite” Kemp. Griffin announces that the first day of the Terror has begun, and that “the Epoch of the Invisible Man” will soon be upon them. He threatens to kill Kemp first to set an example, and ends the letter: “Today Kemp is to die.” Kemp fetches his gun, putting it in his jacket pocket. He declares that he will use himself as “bait” to catch Griffin.
The true extent of Griffin’s megalomania is revealed in this letter. It is clear that the whole point of his “Reign of Terror” is to give himself absolute power over the world, as indicated by the phrase: “Epoch of the Invisible Man.” It seems that Kemp was right to call Griffin insane, as he now appears completely delusional.
Colonel Adye arrives at Kemp’s house and informs him that his servant has been “assaulted.” Adye explains that a note was violently snatched from the servant’s hand. Kemp explains that the note the maid was holding proposed a trap, in which Kemp hoped to use himself as bait to capture Griffin. There is a sound of glass smashing upstairs, and Kemp declares that it’s the window breaking. They hurry upstairs and find Kemp’s study destroyed. More windows smash, and Kemp concludes that Griffin is going to attempt to break every one in the house. He adds that Griffin will fall and cut his feet.
Unlike Griffin, who in Kemp’s words is “pure selfishness,” Kemp himself is selfless. He is happy to use himself as bait, thereby potentially sacrificing himself in order to ensure that Griffin is caught. Given Griffin’s threats to kill Kemp and anyone else who stands in his way, this is a very serious risk. Yet Kemp nonetheless offers for the sake of the greater good.
Adye goes outside, where he confronts Griffin’s disembodied voice. Adye fires into the air, but in the next moment is hit in the face with his own gun. Griffin, still unseen, holds the gun, and demands that Adye go back into the house. From inside, Kemp watches Adye speak to the air and wonders why he hasn’t shot Griffin; at this point he realizes that Griffin must have gotten the gun. Adye begins walking to the house, before turning around in an attempt to grab the gun and missing. Griffin fires a shot and Adye falls to the ground. While Adye lies still, a housemaid and two policeman hurry over.
The climactic fight scene between Griffin and Colonel Adye has a surreal edge to it, since Griffin cannot be seen. Again, further confusion is created through the fact that the reader witness the fight through Kemp’s eyes. Although Kemp is smart enough to quickly realize that Griffin has seized Adye’s gun, the haze of confusion is a reminder of how incapacitated even smart people are by Griffin’s invisibility.
Kemp watches as the gun moves toward the house, and hears Griffin laughing and attempting to hack down the door with an axe. The doorbell rings, and Kemp hastily lets the policemen and housemaid inside. He tells them that Griffin has killed Adye and now has the gun. Kemp gives the policemen each a poker and leads them to where Griffin is attempting to smash the door. One policeman manages to grab the axe with the poker, flinging it from Griffin’s hands. There is a further scuffle in which both Griffin and the policeman are injured. One of them accidently smashes a gas bracket. The policeman suddenly find that both the housemaid and Kemp have disappeared.
The encounter escalates as more people get involved, which doesn’t seem to do much to stop Griffin. The image of him laughing maniacally while hacking through the door with an axe is something of a trope of the horror genre (but it wasn’t yet a trope when Wells was writing). Before the story ends, the characters must confront the antagonist at his most evil and deranged before they are either killed or are finally able to overpower him.