The plot of “The Sniper” involves two snipers positioned across the street from one another, both unaware that the other sniper is his brother. The story takes place in Dublin during the Battle of Dublin in 1922. The Republican sniper takes a bullet in his arm and realizes he needs to get help but is unable to move for fear of being shot again. He creates a ruse by lifting his cap with the muzzle of his gun, creating the impression that he is getting up. In response, the other sniper fires, and stands up, celebrating in the thought that he has just killed a Republican.

The Republican, very much still alive—albeit with an injured arm,—fires an easy shot and kills his enemy. He then climbs down and approaches the body of the sniper that he has felled. As he turns the corpse over, he realizes that he has shot his own brother. This is where the story ends, so the plot does not include his reaction to the realization. We are, however, given insight into how he felt at having shot and killed the other sniper. He is described as feeling revolted at the “shattered mass of his dead enemy.” He feels disgusted with himself, with the war, and with just about everybody. The realization that his victim was his brother transforms his tragedy into a deeply personal one.

Exposition: There is very little exposition in the short story, which begins with a Republican sniper eating a sandwich and drinking from his flask of whiskey. He is on a rooftop overlooking Dublin during the Irish Civil War. The Republican sniper is described as being a young fanatic who is used to looking at death.

Rising Action: The rising action begins when the Republican sniper lights his cigarette, and a bullet from the opposite rooftop strikes the parapet near him. The Republican sniper then shoots and kills a soldier in a turret on the street below, as well as an older woman who was acting as an informant. After killing the two people, the enemy Free Stater sniper shoots and hits the Republican sniper in the forearm. The wounded Republican sniper then creates a ruse by placing his helmet onto his rifle and barely lifting it above the parapet. The enemy sniper then shoots and hits the helmet as the Republican sniper drops his weapon to the street and hangs his arm over the parapet to create the illusion that he is dead.

Climax: The Republican sniper then crawls to the corner of the rooftop, where he aims his revolver at the unsuspecting Free Stater sniper on the opposite roof. The Republican sniper successfully shoots and kills the enemy sniper.

Falling Action: The enemy sniper falls from the opposite rooftop, and the Republican sniper is overcome with grief and emotion. He then decides to look into the face of the enemy sniper and climbs off the rooftop to approach the lifeless corpse on the ground.

Conclusion: When the Republican sniper rolls the body over, he discovers that the enemy sniper is his brother.

"The Sniper" takes place during the Irish Civil War, in the city of Dublin. On an evening in June, a Republican sniper is perched on a rooftop near O'Connell Bridge, eating a sandwich.

Suddenly, he sees a flash in the darkness. He takes a match and lights a cigarette. The flame of his match alerts an enemy sniper to his presence, and the enemy sniper fires at the rooftop. The bullet whizzes past the Republican sniper.

Below, he sees an enemy car and wants to shoot it but he knows that his bullet will not penetrate its exterior. He does, however, shoot and kill an informer and a man who suddenly appears from a turret.

In response, the enemy sniper shoots at the Republican and wounds his arm.

Injured, the sniper knows that he must make his escape but he cannot simply walk away because he risks being shot again. So, he puts his cap over the muzzle of his gun and raises it into the air. The enemy sniper shoots and thinks that he has succeeded in killing the Republican. He then stands up, giving the Republican a clear and easy opportunity to take him down.

The Republican fires a shot and hits his enemy. The lifeless body then falls to the ground below.

As the Republican sniper climbs down from the roof to make his escape, he suddenly wonders if he knows the dead sniper. He approaches the body, turns it over, and is staring into the face of his own brother.

"The Sniper" by Liam O’Flaherty is a short story published in 1923 and set in Dublin during the Battle of Dublin, when the Irish were attempting to free themselves of English rule. The story is told in the third person by a limited narrator who has access to the thoughts, actions, and feelings of the sniper of the title. 

The sniper is sitting on a roof searching for targets. He realizes that an enemy sniper is aware of his position, which he gave away by lighting a cigarette. An armored car drives over the bridge and an old lady walks up to the car. He realizes that the old lady is alerting the car's driver to his position and so he kills both the old lady and the British soldiers without remorse. The opposing sniper sees his muzzle flash and shoots his arm. He lures the other sniper out into the open by pretending to be dead and kills the other sniper.

He feels some kinship to the dead sniper, and "he felt a sudden curiosity as to the identity of the enemy sniper whom he had killed". He makes his way to the corpse. The story ends with the line:

Then the sniper turned over the dead body and looked into his brother's face.