A group of pilots in the Canadian wilderness begin to hear strange reports over their radios about planes crashing, cars stalling, and a deadly plague which has gripped the planet. As the plot continues, it's clear that Earth is in the midst of an invasion. The pilots barracade themselves in a cabin in the woods and wait for impending doom.
USS Iowa is on its final voyage before being decommissioned and turning into a floating museum. When USS Enterprise is attacked and destroyed by a mysterious force, World War III looms. The captain of Iowa chases an invisible ship, which they discover to be an alien force waging war on Earth. Only the crew of this last American battleship, stands in their way. (The Iowa's outdated technology is immune to the electromagnetic pulse (EMP) weapons of the alien.)
Astronomer Shinichi Tachibana, has a secret identity as superhero "Iron Sharp" (changed to "Space Chief" in the English dub) and has many children as friends. When they are attacked by a group of metallic aliens ("Neptune Men" in English), Iron Sharp drives the aliens away. Tachibana is also resourceful, as he helps develop an electric barrier to block the aliens from coming to the Earth. After several losses by the aliens, they announce that they will invade the Earth, throwing the world into a state of panic. As they invade the aliens destroy entire cities with their mothership and smaller fighters. Iron Sharp destroys multiple enemy ships and Japan fires a nuclear missile at the mothership, destroying it.
Taking place three hundred years prior to the events of the first film, the narrator describes how the government knew what was happening. A woman is seen driving recklessly in California while arguing over her cell phone. Police officer Ryan Hadley (Bruce Boxleitner) pulls her over and gives her a warning. The man calls her back, but she tells him off and throws the phone down; the phone then transmorphs into a robotic spider and kills her.
George Herbert explains that despite years of searching for extraterrestrial life, mankind never expected the invasion which devastated human civilization into anarchy, and that the aliens were killed by a lack of immunity to the bacteria in the human blood they consumed. Two years later, a town is seen, populated with silent refugees including characters Shackleford and Sissy. Suddenly, three Tripods land in the city. People are struck by a Heat-Ray. Shackleford takes a sample of Sissy's blood, with which he injects himself.
In February 1942, U.S. armed forces defend Los Angeles from unidentified flying objects. Seventy years later, the alien invaders return to finish the attack.
In 2009, a race of aliens piloting giant robots have conquered Earth and forced humanity to live underground. They have done this by altering the environment, causing constant rainfall and darkness. Over 300 years later, after many generations of living underground, a small group of human rebels plan to finally take back their world from the mechanical invaders. They soon learn however that the aliens do not pilot the robots, but are the robots.
Deux frères, Jimmy et Kamango, tentent de survivre à une catastrophe planétaire. Des « choses » ont envahi le monde. Elles se nourrissent d'êtres vivants, y compris d'êtres humains. Les deux frères logent désormais dans l'appartement d'un ancien militaire, Kuter, toujours accompagné de son garde du corps. Alors que les deux frères rêvent de partir en direction du sud, une femme muette fait irruption dans leur vie…