What is the story mode in gta iv?

Grand Theft Auto IV’s story mode is a single‑player narrative set in the fictional Liberty City, modeled after New York City. The campaign follows Eastern European war veteran Niko Bellic, who has come to the city in search of a better life but finds himself drawn into the clutches of high‑profile criminals. Throughout the mode, players guide Niko through a series of missions that explore his efforts to escape his past and the pressures he faces from the criminal underworld. The open‑world design allows players to roam freely across the city’s four boroughs and the neighboring state of Alderney, but the core experience remains a linear progression of story missions that advance Niko’s personal journey.