Random Characters are minor characters found standing on the street in Grand Theft Auto IV, its episodes, and Chinatown Wars. Their presence is indicated by a small blue person icon on the radar, but only when within close proximity to the player. They provide Niko, Johnny, Luis and Huang with small storylines and minor missions.
The achievement/trophy"No More Strangers" for GTA IV involves locating all of them and helping each one out at least once. Most of the random character missions are required for 100% completion.