The narrative of “The Secret Life of Walter Mitty” weaves in and out of reality. In order to escape his mundane existence as a henpecked husband, the titular character fantasizes different scenarios in which he is a hero. Throughout the story, Walter Mitty experiences five vivid daydreams of his secret life as a more masculine and powerful alter ego.
The short story opens with his first reverie as Commander Mitty, a veteran daredevil navy captain who leads his aircrew through a harrowing storm. After his strategy saves their SN202 hydroplane, he is commended by his admiring crew:
The Old Man’ll get us through. … The Old Man ain’t afraid of Hell!
In reality, Walter is merely driving his wife to her hairdresser appointment. Apparently his alter ego overtakes his true identity as he drives too fast for Mrs. Mitty’s liking.
After they arrive at her hairdresser, Mitty's domineering wife nags him to purchase overshoes for himself. After she tells him to wear gloves, like a child, Walter imagines himself as highly respected surgeon. In this second daydream, he dons surgical gloves and swoops in to help other physicians. They revere him as a brilliant surgeon whose published work they admire. In the operating room, they desperately need his help to fix the “anaesthetizer” machine and save a millionaire banker. Even better, he is asked to step in and take over the operation for the other surgeons, which he heroically does. In reality, though, Walter is parking his car and nearly hits another one in the lot.
After buying overshoes, Walter tries to remember what else his wife demanded him to buy while waiting for her hair appointment to finish. In his third daydream, he fancies himself an expert sharpshooter with an injured right arm. In this scenario, Walter is a rakish hero who not only “gets the girl” but also saves this damsel against another man. In reality, though, he is just talking out loud to himself and remembering to buy puppy biscuits.
When Walter sits in a hotel lobby—he needs to be there waiting for his wife as she expects—he picks up a magazine and sees a cover article on the war with Germany, which takes him back to his first daydream as a naval commander living dangerously. He soon enters his fourth daydream—as Captain Mitty, carefree and unfazed by enemy gunfire. Despite being closed in on the enemy, he is nonchalant. After finishing a brandy, he walks to the door of the dugout and waves to the sergeant, brazenly facing the enemy and his fate.
The fifth and final daydream extends from this fourth daydream. After his wife instructs Walter to wait a minute for her—in the rain on the sidewalk when she needs to duck into a drugstore—he imagines himself as the doomed Captain Mitty, who now is actually named Walter Mitty.
He took one last drag on his cigarette and snapped it away. Then, with that faint, fleeting smile playing about his lips, he faced the firing squad; erect and motionless, proud and disdainful, Walter Mitty the Undefeated, inscrutable to the last.
This leaves readers with several questions: Has poor Walter given up? Does the firing squad represent his wife? Is he ultimately trapped in his dreary real life? In the end, though, perhaps Walter has won; after all, he has his secret life. He is defiant, “undefeated,” and “inscrutable.” His wife has no knowledge about and cannot take away Walter’s alter egos.