In the story, the main character is a daydreamer. Here's the basics of the plot, according to Wikipedia:
The short story deals with a vague and mild-mannered man who drives into Waterbury, Connecticut, with his wife for their regular weekly shopping and his wife's visit to the beauty parlor. During this time he has five heroic daydream episodes. The first is as a pilot of a U.S. Navy flying boat in a storm, then he is a magnificent surgeon performing a one-of-a-kind surgery, then as a deadly assassin testifying in a courtroom, and then as a Royal Air Force pilot volunteering for a daring, secret suicide mission to bomb an ammunition dump. As the story ends, Mitty imagines himself facing a firing squad, "inscrutable to the last." Each of the fantasies is inspired by some detail of Mitty's mundane surroundings:
- The powering up of the "Navy hydroplane" in the opening scene is followed by Mrs. Mitty's complaint that Mitty is "driving too fast", which suggests that his driving is an action of the daydreaming and he has lost touch with the actual world.
- Mitty's turn as a brilliant surgeon immediately follows his taking off and putting on his gloves (as a surgeon dons surgical gloves) and driving past a hospital.
- The courtroom drama cliché "Perhaps this will refresh your memory," which begins the third fantasy, follows Mitty's attempt to remember what his wife told him to buy, when he hears a newsboy shouting about "the Waterbury Trial" ("You miserable cur" are the last words mentioned in the fantasy. Mitty was supposed to buy puppy biscuits.)
- Mitty's fourth daydream comes as he waits for his wife and picks up an old copy of Liberty, reading "Can Germany Conquer the World Through the Air?", and envisions himself fighting Germany while volunteering to pilot a plane normally piloted by two people.
- The closing firing-squad scene comes when Mitty is standing against a wall, smoking.
He's an amazing daydreamer, able to take mundane situations (like going to a beauty parlor with his wife) and turn them into harrowing adventures. However, Walter has almost lost touch with reality, which brings about bigger conflicts in this story.
Another book I'd like you to consider is Harold and the Purple Crayon by Crockett Johnson. It was written in 1955.
The plot, according to Wikipedia:
The protagonist, Harold, is a curious four-year-old boy who, with his purple crayon, has the power to create a world of his own simply by drawing it.
Harold wants to go for a walk in the moonlight, but there is no moon, so he draws one. He has nowhere to walk, so he draws a path. He has many adventures looking for his room, and in the end he draws his own house and bed and goes to sleep.
Both of these stories show major daydreamers. In both stories, the daydreams are much bigger than reality, and thus, the character wishes to stay in that daydream. It also causes conflict in the real world, since the character prefers the make believe situations. Thus, they're straddling reality and fantasy, and not doing it well.
When writing about daydreamers, they need to prefer fantasy, which should be more enticing than reality. Thus, the conflict, a writer's friend.
Even though both of these books are rather old, they're still great entertainment. That's the goal for every writer--to entertain through conflict and resolution.
So go, daydream, and live the life of a fantasy!
Have a great day!