In most of these stories, Earth is invaded by, or is involved in a conflict with, an alien race.
“The Epsilon Directive” by David Bruns
The war with the Scythians is essentially over; their fleet’s been destroyed and they’ve scattered. Epsilon Units are hunting down the last Scythians and killing them. Noog finds himself in one of these squads, even though he was against the war. He succumbed to family pressure and joined anyway. When they scan Talos 5 for Scythian life signs, they get a hit.
This story can be read in Best of Beyond the Stars. (17% into preview)
“Bloodchild” by Octavia E. Butler
Gan and his family are humans living in the Preserve on another planet. It’s ruled by the Tlic, an insect-like species. On the last day of Gan’s childhood, the family is visited by T’Gatoi, a Tlic politician in charge of the Preserve. Humans and the Tlic have an arrangement—they’re protected in the Preserve in exchange for incubating the Tlic eggs. Gan has been chosen by T’Gatoi.
This isn’t technically an invasion story, as the humans aren’t living on Earth, but the relationship between the two species has a similar dynamic.
Most of this story can be read in the preview of the anthology Invaders!
The following five stories are also in the Invaders! anthology.
“Guesting Time” by R. A. Lafferty
There are several hundred people waiting at the office of Immigration and Arrivals. No arrivals were scheduled and no ships have landed. The crowd says they’re from Skandia. They’re inexplicably multiplying. Apparently, they’re from a planet that is overpopulated.
“Roog” by Philip K. Dick
Early in the morning, a dog watches the activity around his house. He sees a “roog” approaching the gate. The dog tries to defend its home and warn those inside. The owners, the Cardossis, don’t respond to his warning.
This story gives a dog’s perspective of an “invasion”.
“The Liberation of Earth” by William Tenn
The narrator recounts the story of Earth’s first liberation. An enormous space ship landed in France. A tripodal, twenty-five foot tall alien emerged and made an hour long speech no one could understand. A linguist managed to establish communication. They were the Dendi, a highly advanced civilization. They were fighting the Troxxt, an immoral, wormlike race that were coming for Earth next. The Dendi wanted to establish a base on Earth.
“To Serve Man” by Damon Knight
Earth is visited by the Kanamit, a half pig and half human alien race. They bring gifts—ways of increasing food production, power generation, and other helpful things. Some people question their altruism, so the Kanamit are subjected to a lie-detector.
This story can be read in the preview of Far Out. (10% into preview)
“Idiot Stick” by Damon Knight
A huge alien ship lands in a New Jersey meadow. A stick-bodied man steps out. Earth’s military forces quickly converge on the area—tanks, helicopters and a destroyer. The visitor is from the Galactic Federation and expresses peaceful intentions. The Federation wants to establish a center on Earth and is willing to pay for the land and the human labor to build it. The alien disperses a cloud of glittery objects among the crowd. Partaking of one of them produces a feeling of happiness.
This story can be read in the preview of Far Out. (40% into preview)
The following four stories are in the anthology Invasions.
“Imposters” by Philip K. Dick
Spence Olham has been working on the Project—an offensive weapon for the war effort—for ten years. Earth has been attacked by the Outspacers, who easily made it around Earth’s cruisers. A stable defense has been established, but an effective offense hasn’t yet been mounted. On their way to work, Olham and his colleague Nelson are accompanied by Major Peters, who’s with national security. Olham is shocked by what he’s told.
“The Cloud-Men” by Owen Oliver
The UK has only one newspaper, controlled by the government. This is no time for conflicting opinions. Marriage is mandatory for most adults. There are regulations around where people can live. The cause of all these measures is the Cloud-Men. John and Mary Pender are the only two people who’ve had a confirmed interaction with them. The newspaper relates their story. It started in late August when thick clouds descended toward Earth, causing a great darkness.
“Don’t Look Now” by Henry Kuttner
A man in a brown suit, a reporter, drinks in a bar. Another patron, Lyman, has been talking to him for a while. He claims that an alien was just sitting right next to the guy. The reporter didn’t see anything. Lyman says the Martians rule the world. They tell people what to do, but no one can remember. Lyman’s brain was scrambled, so he’s not susceptible to their influence.
“The Certificate” by Avram Davidson
Roger Freeman is up early before work and standing in front of the great door. He’s here to put in a request. The last one he submitted hasn’t been answered yet after two years. The Hedderans have been ruling Earth for fifty years. There aren’t a lot of humans left. Punishments for disobedience are severe.