Mars, which has been settled by African Americans twenty years earlier.
Willie Johnson - Martian settler seeking revenge on his parents' death by lynching.
Hattie Johnson - Wife of Willie Johnson.
Three unnamed sons - The Johnson children.
Elizabeth Brown - Neighbor of the Johnsons.
Mr. Brown - Husband of Elisabeth Brown who harbors no desire for revenge.
Trolley operator - Approves of the White section painted for his trolley.
Mayor - Tries to prevent the mob forming around Willie Johnson.
Dr Phillips - One of the men who killed Willie Johnson's parents many years ago.
Mr. Burton - One of the men who killed Willie Johnson's parents many years ago.
Old Man - Spokesperson for the first rocket of white people to land on Mars.
Willie Johnson, who wishes revenge for his parents' death at the hands of white racists on Earth.
The unnamed old white man who arrives in the rocket and asks for mercy on behalf of Earthians.
The old man explains that the people and places where Johnson's parents were killed are now all gone.
Johnson backs off from his revenge, deciding it's time for a new start.
The main theme is the emptiness of revenge: twenty years after the fact, Willie Johnson still remembers the death of his parents and cannot forgive the white people responsible. However, related to this is the theme of bigotry: that it can assert itself anyplace where there is a majority that can oppress a minority. As part of these themes, we see the danger and allure of mobs as a way to promote dangerous ideas, to play upon the baser instincts of humans.
The children of Hattie Johnson are excited at the news of a white man arriving on Mars. Hattie hadn’t seen any white men since the Negroes moved to Mars twenty years earlier, settling down on a new planet while the old planet waged war on itself and its inhabitants blew each other up. She tells the children to stay behind and checks in on Elizabeth Brown’s house, down the line; she sees the Browns in their car, getting ready to see the white man. When Hattie asks if they’re planning to lynch the white man, everybody laughs at the notion.
Hattie’s husband Willie then drives by in his car, with a very different opinion: he’s going home to get guns, remembering how his father was hung on Knockwood Hill by Dr. Phillips and Mr. Burton, while his mother was shot to death. Hattie asks if the white people would be allowed to live on Mars, and Willie says they’ll live in the same conditions the Negroes faced backed on Earth, now that the shoe’s on the other foot. At home, Willie gets the guns from the attic; the children ask their father about the white man and he locks them in the house. He gets a bucket of paint and stencil from the garage, as well as a rope which he ties into a hangman’s knot.
He and Hattie leave to meet the rocket, and Hattie sees other cars with guns; Willie had spoken with them on his way home. At the landing area, Willie hands out guns and then stops a trolley, where he paints a sign for Whites to sit in the rear section. He calls together people to paint similar signs on all trolleys, rope off the last two rows of theaters for whites, and calls to enact laws barring interracial marriage and enforcing a minimum wage for whites. The mayor protests at all this action, but Willie only tells his mob that they’ll elect a new mayor.
The rocket lands and an old white man emerges. He doesn’t give his name but explains how a third world war began after the Negroes left for Mars and ended only last year. The major cities of the world were burned, and as he listed the places that were destroyed, the gathered crowd responded to places that were familiar to them. When he mentions Greenwater, Alabama, Willie responds; it was where he was born. The old man continues and admits to the stupidity of those still on Earth, that they’re willing to work for the Negroes of Mars in the humblest positions, if only they’ll be allowed to come here.
Hattie senses that Willie is the key to stopping the mob from acting violently. She asks about Knockwood Hill in Greenwater, and the old man speaks to someone inside the rocket and pulls out photos of how the hill and the oak tree where his father was lynched have both disappeared. The men who killed Willie’s father are dead, the trees have all burnt, the houses of everyone are gone. Willie remembers Earth and realizes it’s all gone; he drops the rope he’s holding. He decides it's time for a new start. On the drive home, Willie talks about how the white man is now as lonely as the Negroes had long been, and now they can all start over on the same level. At home, Hattie lets out the children, who ask Willie if he saw the white man. Willie say that for the first time, he’d seen the white man with clarity.
Bradbury sees this story as best paired with the story "Way Up in the Air" from The Martian Chronicles, which shows an actual exodus from Earth to Mars by African Americans tired of racism on their home planet.