Fallout 3, often referred to by its development codename Van Buren, is a canceled role-playing video game developed by Black Isle Studios. It was intended to be the third game in the mainline Fallout series before its cancellation in 2003. Set in the year 2253, the plot of Van Buren revolved around an escaped prisoner who would explore the American Southwest while pursued by robotic prison guards. The main antagonist was a mad scientist named Victor Presper, who planned on using the prisoner as an inadvertent vector to spread a deadly virus. Gameplay would have included a mixture of real-time and turn-based combat. The player would explore the map with a team of non-playable character (NPC) companions. Each NPC would make their own independent decisions which would affect the story.