The Brown Streak is a fictional superhero in Grand Theft Auto IV. The name of a film starring him, The Brown Streak Returns, implies that comic books, movies, or television shows have revolved around him previously. In The Ballad of Gay Tony, Luis Lopez has a small action figure displayed on the table holding his TV and Yusuf Amir has a life size statue of him.
Like the Brown Streak train, the superhero's name is another example of toilet humour from Rockstar.
The Brown Streak Returns tag-line is: THEY TRIED TO WIPE HIM OUT...BUT THEY MISSED A BIT...
The Brown Streak may be a reference to the superhero, Silver Streak.