Niko Bellic is a war veteran from Eastern Europe who comes to Liberty City in search of the American Dream, and to escape his troubled past. Niko grew up in a small village in Yugoslavia, where he fought in the Yugoslav Wars as a teenager. These traumatic experiences shaped Niko's cynical outlook on life and left him struggling with PTSD.
Niko travels to Liberty City at the behest of his cousin Roman, who falsely claims to be living a life of luxury. In reality, Roman is heavily in debt to local mobsters. Niko begins working for Roman's loan shark in an effort to pay off his debts, and is quickly drawn into the city's criminal underworld.
Niko becomes acquainted with characters like Playboy X, Dwayne Forge, and Ray Boccino, carrying out jobs for them in order to make a living. However, Niko becomes disillusioned with the criminal lifestyle over time. He forges friendships with characters like Little Jacob and Brucie, who provide a respite from the darkness that surrounds him.