Fifteen Man Squad

The Fifteen Man Squad
The "fifteen man squad" was a squad (proper name unknown) of child soldiers during the Bosnian War. Members of this squad included Niko Bellic, Florian Cravic, Darko Brevic, Goran, Mijo, Dragan, Dmitar, and eight other unnamed members. All had grown up together in the same village.

Sometime during the war, the squad was ambushed by enemy forces; Niko escaped. He believed that the squad could not have been ambushed unless someone within the group had sold them out; he travelled back to where the ambush had taken place, and saw a large pit with the squad members dead inside. After picking through the bodies, Niko realised that two others were missing: Florian Cravic and Darko Brevic.

Concluding that one of the two had been the traitor within the squad, Niko vowed to track down and kill the culprit. Unknown to Niko, Florian would flee to Liberty City, and Darko to Bucharest, Romania.

Roughly ten-to-thirteen years later in 2008, Niko arrived in Liberty City, both to visit his cousin Roman, and to track down Florian Cravic, whom he had learned was living there. Eventually, Niko tracked Florian down — the latter had come out as homosexual, and was having a fling with Liberty City's closeted deputy mayor, Bryce Dawkins. He protested his innocence, and Niko was angered to know that he would not get his revenge any time soon — he had no idea where Darko Brevic could be.

Later in the game, an agent of the United Liberty Paper Company located Darko as a favour to Niko, and had him kidnapped from Bucharest, and left at Francis International Airport. Niko confronted Darko, and discovered that Darko had sold the squad out for $1,000 to fund his heroin addiction. Niko was all the more appalled that he and his friends were sold out over such a paltry sum; Darko called Niko a hypocrite, knowing that Niko had frequently killed for money too. He also told Niko that Goran had killed Darko's friends and neighbours, giving Darko another reason to betray the unit.

The decision to kill Darko or let him live is then left to the player.

Script
(Darko is thrown out of the back of a van by United Liberty Paper informants. The van drives off, and Niko and Roman approach the bound Darko)

Niko: You remember me?

Darko: Пусти ме. Не познаја те. '''(Leave me alone, I don't know you). '''I don't know you.

(Niko leans down and grabs hold of Darko)

Niko: Yes you do. I'm the one, who survived.

Darko: (chuckles) Niko... hello.

Niko: Рећи ми зашто (Just tell me why).

Darko: Зашто? (Why?)

Niko: Зато што сво били пријатељи. Сви смо одрасти заједно. Дмитар, Драган, Горан, Мијо... могу да настави свијо, ха? (We were friends. We were all friends. We all grew up together... Dmitar, Dragan, Goran, Mijo... should I go on and name them all?)

Darko: We were friends, but I had other friends!

(Darko rolls away from Niko and struggles to stand with his hands still bound behind his back)

Darko: Friends that Goran and his guys killed. My fucking neighbours!

(Darko approaches Niko and gets in his face)

Darko: Because of what? Because of shit!

(Darko turns and walks towards Roman getting in his face)

Darko: Lies. Fucking lies!

Niko: So that makes it ok. To stab your friends in the back?

(Darko stumbles back)

Darko: When eveything you believe is shown to be shit, you make strange choices I guess.

(Niko grabs Darko and pulls him closer)

Niko: Fuck you! Strange choices? How much?

(Darko laughs and stumbles back)

Darko: A thousand.

(Niko lets go and steps back, distraught)

Niko: You killed my friends for one thousand dollars?

Darko: How much do you charge to kill someone?

Niko: You ruined me, you fuck!

Darko: I needed the money... I had problems.

Niko: You're a fucking junkie!

(Darko falls to his knees)

Darko: (shouting) Kill me then! You fucking hypocrite. Trust me, you'll be doing me a favour! (Screams)

Roman: Niko -- come on, let's go. Let him suffer... he knows what he did. He doesn't look like he enjoys life too much.

(Darko continues crying, struggles and stands again)

Conclusion
If the player chooses to kill Darko, Niko will shoot him 12 times, one shot for each fallen squad member. Before dying, Darko will thank Niko.

If the player lets Darko live, he runs off, never to be seen again. Niko is angry with himself for letting Darko live, but eventually decides that it was the best choice, and feels better. He lets Florian know, and Florian tells Niko he's proud of him. Niko finally has closure on that part of his past.

Trivia

 * In a conversation with Dwayne Forge during an activity, Niko reveals that eight of the twelve squad members that died were friends of Niko, the other four merely being acquaintances from the village.
 * If the player decides to execute Darko with a Desert eagle (which holds a capacity of 9 bullets) Niko will still shoot Darko 12 times without reloading.