During the astronomical opposition of 1894, when Mars is closest to earth, a number of observatories spot a flash of light emanating from the red planet’s surface. Night after night, the planet seems to ignite for a moment. The narrator himself witnesses this through a telescope owned by his friend, an astronomer named Ogilvy. Although both men are excited, Ogilvy assures the narrator that it’s quite unlikely there are living beings on Mars. The local newspapers, for their part, are slow to report on the anomaly, and when they do, they don’t ascribe much significance to it.
In the small hours of morning after many consecutive nights of the strange Martian flashes, a greenish flame sweeps across the sky and crashes into a sandpit near Ogilvy’s house in Horsell, England. Thinking he’s seen a meteor, he rushes outside to find the object. When he arrives, he finds a large cylindrical mass embedded deep in a crater caused by its own impact. As he watches, the end of the projectile begins to unscrew, and he sees what he thinks are men, half burnt to death, trying to escape from inside. Scrambling out of the pit, Ogilvy runs toward Woking, where he meets a wagoner who ignores him because he looks and sounds insane. Finally, Ogilvy finds Henderson, a journalist from London who quickly follows him back to the pit before sending a telegraph to London.
Slowly but surely, the cylinder from Mars attracts large crowds, which stand around the edge of the pit waiting for something to happen. It seems the cylinder is about to open when the heavy lid finally falls to the ground, causing the panicking crowd to go quiet. From the dark cavity emerges a dark, greyish creature, about the size of a bear, with “luminous discs” for eyes and snake-like tentacles. Just as this creature emerges into the pit, a new one appears in the opening of the cylinder, at which point the narrator sprints toward the trees for cover. Looking back, he sees the head of a man who had fallen into the pit try to escape before suddenly falling backward with a scream.
While the narrator slinks through the woods—too afraid to go near the pit—a group of men (including Ogilvy and Henderson) approach the cylinder with a white flag. As they near the Martians, a blinding light jumps forth and incinerates them. The crowd breaks into terror as the Martians start wreaking fiery havoc on Horsell Common, burning people and trees and everything in the vicinity. The narrator goes home, where he finds his wife and tells her everything he’s seen. He and his wife sit down to dinner and eat a calm meal while he assures her that the aliens won’t harm them because the force of gravity on earth is too strong to allow Martians to roam freely across its surface. This seems to quell both his and her nerves, despite the fact that the narrator obtained this information from Ogilvy, who has just been killed by Martians.
The next day, with the memory of the Martians fresh in their minds, the narrator’s fellow Englishmen surprisingly go about their everyday duties. Some people talk about the disaster excitedly, as if discussing entertaining current events. Meanwhile, a group of soldiers approaches Horsell Common and establishes a perimeter around the pit. Late that night, another cylinder falls from the sky, landing not far from the first. The next day, fighting breaks out between the humans and the Martians, and it quickly becomes clear that human weapons are no match for the Martians’ Heat-Ray. The narrator and his wife decide to escape to the house of some relatives in Leatherhead, a short trip from their home in Woking. The narrator goes to a nearby inn and borrows a horse and a cart, which he uses to transport his wife to Leatherhead before turning back to Woking to give back the horse, having promised the innkeeper to have it back by midnight. By the time he makes it back to Woking, however, a third cylinder has arrived, and he looks up from the road to catch sight of a terrifying image: a large machine with three legs towering in the distance. The machine goes about smashing everything in its way while firing a Heat-Ray, and the narrator abandons the horse. Not long after, he finds the innkeeper’s dead body, and then makes his way to his own house, where he takes refuge for the night.
While hiding in his house, the narrator meets an artilleryman who has fled the pit and stumbled onto his property. The artilleryman tells him about the destruction wrought by the Martians and their fighting machines. The two men decide to set out together, the narrator wanting to meet up with his wife in Leatherhead, the artilleryman hoping to meet up again with his battery. On their way, they encounter scores of people running madly from five fighting machines, which discharge their Heat-Rays, torching everything around them. Realizing that water will protect him from the Heat-Ray’s blasts, the narrator jumps into a stream, and others around him follow suit. At the same time, a large gun hidden by military fighters fires a shot that explodes in the face of one of the fighting machines. This shot takes down the machine, and the other machines flock to their fallen comrade before unleashing total fury onto the landscape with the Heat-Rays. The narrator passes out on the riverbank, narrowly avoiding getting stepped on by a machine before he’s left alone.
The fighting machines return to their pit in Horsell Common, pulling their dead friend along with them. Meanwhile, the narrator notes that a new cylinder arrives every day, and the Martians grow increasingly powerful as they build their machines, which apparently can also discharge a deadly black smoke. During this time, the narrator wanders through the woods and eventually comes upon a frightened, hysterical curate, who asks the narrator what sins they could have committed to deserve such a punishment. The narrator responds by telling the curate to be a man, and asks what religion is good for if it “collapses under calamity.” Although he dislikes the curate, the narrator agrees to travel with him, and they set off so as to avoid encountering the Martians again.
At this point, the narrator tells the story of his brother’s experience during the Martian invasion. A medical student in London, his brother doesn’t hear about the Martians’ arrival for several days. When he finally does, he decides to visit his brother in Woking, hoping to see the aliens before they’re killed by military forces. When he goes to the train station, however, he learns that no trains are running in that direction due to an accident. Throughout the next day, he buys multiple newspapers in an attempt to gather more information about the invasion. When all at once Londoners are told to evacuate the city, he steals a bike from a ransacked cycle shop and rides out of town, eventually coming upon two women getting robbed. After he fends off the criminals, the brother joins these women in their carriage, and the three of them decide to combine their money in order to buy tickets out of the country on a boat. The brother’s story concludes as he sails into the distance while watching an extravagant battle between a warship called the Thunder Child and three Martian fighting machines.
As the narrator’s brother escapes England, the narrator and the curate continue their travels, eventually finding a well-stocked kitchen in an abandoned home. As they sit in this dark place, the sky lights up green and a huge crash sounds, ruining the house and knocking the narrator onto the floor, where he lies unconscious for several hours. When he comes to, the curate tells him to be quiet because the Martians are right outside. Apparently, a new cylinder has arrived, landing almost on top of the house in which they’re hiding and disabling them from leaving.
Over the course of fourteen days, the narrator lives in hiding, afraid to even speak in full volume to the curate. They periodically sneak from the pantry to the kitchen and peer through a hole in the wall. This is how the narrator learns that the Martians feed by extracting the blood of living humans, emitting a strange howl all the while. Although the kitchen contains some provisions, the narrator realizes that they’ll soon run out of food. The scarcity of rations is exacerbated by the gluttonous curate, who is constantly stuffing his face. Hoping to increase their chances of survival, the narrator implements a rationing scheme, cutting the curate off when he’s had too much. This deeply upsets the curate, who grows more and more unhinged until, finally, he has lost his mind. When the curate begins making too much noise, the narrator knocks him unconscious, but it’s already too late; a Martian appears at the hole in the wall. Quickly, the narrator retreats to the coal-cellar, where he shuts the door and covers himself with coal. The Martian eventually creeps toward him and opens the door but doesn’t notice him. It isn’t until several days later that he dares to venture out of the cellar, only to find that the curate is dead and the Martians have moved on.
Out in the open again, the narrator once more encounters the artilleryman, who tells him what has happened in the past couple of weeks. “We’re beat!” he insists, going on to explain to the narrator that the Martians seem to be developing flying machines. Under these circumstances, the artilleryman has resolved to live the life of a “rat,” admonishing fellow humans who don’t have what it takes to survive. He tells the narrator of his plan to tunnel his way into the sewers of London, where he’ll live with a community of like-minded people—including the narrator—until perhaps one day he can learn how to hijack one of the Martians’ fighting machines. Impressed by how well-thought out this plan seems, the narrator accompanies the artilleryman back to a house, where the two men work for hours digging in the basement in order to intersect the sewer system. However, the narrator slowly realizes the artilleryman’s plan is doomed to fail, and he leaves the next morning, setting off for London.
When the narrator arrives in the city, he finds it desolate. The Martians have taken over all of London and their machines now stand tall and powerful throughout the city. A ghostly howl echoes through the streets as the narrator makes his way toward a fighting machine. To his surprise, it does nothing, simply standing still as he approaches. Finally, he comes upon a huge mound at the top of a hill where the Martians seem to have made their largest dwelling area yet. As he looks up at one of the enormous stationary machines, he sees red weed and decay seeping out of the cockpit, and realizes that the Martians must have died of a bacterial infection. In the weeks, months, and years that follow, the world learns that the immune systems of these otherworldly creatures weren’t prepared to defend against earthly bacteria, so their bodies couldn’t handle the infection. In the wake of the Martians’ short stay, humanity rebuilds itself, but the narrator warns against relaxing into a state of comfort, reminding readers that the invaders could come again. Next time, he hopes the human race will be more prepared.