Grand Theft Auto IV is played from a third-person perspective in an open world environment, allowing the player to interact with the game world at their leisure. The game is set within the fictional state of Liberty City, which is heavily based on New York City.[note 1] The single-player story follows Niko Bellic, a veteran of an unnamed war in Eastern Europe who comes to the United States in search of someone important, but quickly becomes entangled in a world of gangs, crime, and corruption. An online multiplayer mode is included with the game, allowing up to 16 players to engage in both co-operative and competitive gameplay in a recreation of the single-player setting.[note 2] Two expansion packs were later released as downloadable content for the game, The Lost and Damned and The Ballad of Gay Tony, which both feature new plots that are interconnected with the main Grand Theft Auto IV storyline, and follow new protagonists.
Development began shortly following the release of Grand Theft Auto: San Andreas. Upon its release, the game was acclaimed by many reviewers who praised its story missions, setting, and updates from previous games in the series. A commercial success, Grand Theft Auto IV broke industry sales records by earning US $500 million in the first week of its release.
Its successor, Grand Theft Auto V, was released on 17 September 2013, and has also received universal critical acclaim.