The stage takes place in the headquarters of an unknown evil group. The room is made of bricks, with two circular doors at each end and red curtains adorning the sides. There's a two-level raised platform on the center with a door marked with a black logo. Unknown military soldiers, possibly Shadaloo Soldiers, can be seen formed at the platforms and in the background. At each side of the stage stand the second-to-last bosses from Forgotten Worlds, Whodin and Laidin, holding an Earth and a Moon above their heads; and in the top center stands a gigantic, shadowy version of the game's final boss, Celestial Emperor Bios.
Two other characters, one with a large claw and another with white hair and a mask, stand in the middle, and periodically several screens appear on the background displaying a number of unknown characters. All these characters appear to have been created specifically for this stage.
Chun-Li's ending takes place in this stage, where she tries to face M. Bison but ends captured instead. Bison states he plans to make her a member of Shadaloo, but fortunately Shadow appears and forces Bison to flee, saving her.
- Headquarters of Evil has the distinction of being the only Capcom stage based on a series with no playable character representation, instead being represented only by a Special Partner, Unknown Soldier.