A planet far from Earth.
Captain Hart - Captain of a rocket exploring outer space.
Lieutenant Martin - Second in command of the rocket.
The Man - The euphemism used to describe the Messiah.
Mayor - Had a withered arm healed by the Man.
Burton - Captain of a rival rocket, killed by a cosmic storm.
Ashley - Captain of another rival rocket, also killed by a cosmic storm.
Survivor - Crewman of Burton's rocket who brings news to Hart of what happened with Burton and Ashley.
Captain Hart, who refuses to believe that the Man - that is, the Messiah - has arrived on a planet he is visiting.
Lieutenant Martin, who believes the Man has come and chooses to side with the planet's people.
Captain Hart leaves the planet to seek out the Man.
The Man is still on the planet, and Martin is taken to meet him.
The main theme is the role of faith in gaining redemption. The Man is what the Judeo-Christian faiths would term the Messiah or Savior, but Bradbury opts to make this a broader, explicitly stating that this figure exists in many cultures and goes by many names. What the Man brings, however, is a sense of peace and happiness that is akin to what the Judeo-Christian faiths would call redemption - that is, a forgiveness of sins and a more enlightened way of life.
Captain Hart is faced with the possibility of this redemption, but makes two mistakes: first, he initially refuses to believe; second, when forced to believe by circumstances, he thinks he can take control of the situation with force. Faith isn't about taking control, after all, but releasing control and allowing a higher power to lead the way. What Hart feels, then, isn't faith at all, but a kind of agnostic desperation.( Agnosticism is a non-committal attitude to the existence of God: neither atheistic nor believing in God, but instead waiting for solid proof to sway one's position.)
Captain Hart is surprised when his rocket's landing on a new planet hasn't received any attention from the planet's people. He made the rocket's presence clear to them yet they don't seem to care. His lieutenant Martin is sent to the nearest city and returns with the news that the people simply aren't interested in the rocket, as there were other concerns: a man for whom these planet's people had waited arrives yesterday. Captain Hart first thinks it's Ashley or Burton, the captains of rival rockets also exploring this part of space, but Martin assures him that isn't the case. Rather, Martin explains in a circuitous fashion, it's the Messiah, who goes by different names in different cultures.
Captain Hart and Lieutenant Martin go to the city, where they are greeted by the mayor. The mayor assures the captain that the man who arrived yesterday was indeed the one Martin spoke of: that there were many witnesses of his arrival and he healed many people of their afflictions, including the mayor's son's withered arm. The Captain refuses to believe any of the proof presented to him, claiming it could have been faked. Martin has had enough of the Captain's disrespect, however, and tells him to stop. Captain Hart tries to threaten him, but Martin calmly states he's staying on this planet. The Captain tries to reason with him, telling Martin that the appearance of this mysterious man is probably a ruse set up by Burton - a dirty trick from a dirty person. Martin seems to relent and returns to the rocket.
Captain Hart returns to the rocket after interviewing more people: he is now convinced it was the work of Burton in an attempt to beat him out of the contracts. Martin says he'll kill Burton, but the Captain makes him promise not to do anything violent, that this is all just part of their business. Two rockets then landed, Burton's and Ashley's. An injured man from Burton's ship comes out: both ships ran into a cosmic storm, Burton died two days ago, Ashley died an hour ago, and there are only three survivors left. Captain Hart tries to make sense of this information and suddenly grows weak; with Martin's help, he returns to the city.
Several hours later, the captain had listened to thousands of accounts in the mayor's auditorium. He asks the mayor if he know where the man went, but the mayor claims he doesn't know. Captain Hart believes the mayor is hiding him and threatens the mayor with his fun. The gun fires, wounding the mayor's arm. The mayor says that Hart never believed and now he's hurting people because he thinks he believes. Hart says he will hunt down this man on another world, and will eventually catch up. Martin says he's staying on the planet but agrees to walk Hart to the rocket; when they get there, Martin asks what Hart will asks the man when they finally meet. Hart says he'll ask for a little peace and quiet, that's it been too long since he's relaxed. When Martin asks if Hart would simply try, Hart doesn't understand. Of the rocket's crew, only three others will accompany the captain, while seven will remain with Martin on-planet. After the rocket leaves, Martin is greeted by the mayor, who pities Hart for a quest that he'll never fulfill. The mayor then leads Martin and the others to the city to meet the man.