Ada Wong (エイダ・ウォン Eida Won?) is the pseudonym of an enigmatic unnamed spy of Asian-American descent. She has gained notoriety in the corporate world for being able to handle serious situations and the most difficult requests without guilt. She acted secretly in the background of many biohazard incidents and collected information which became useful to several organisations, while at the same time operating to undermine them. However, Ada follows only her own "true purpose" and has often betrayed the organisations and customers she is affiliated with to achieve it.
Ada's personal life is a complete mystery. Her ethnicity and nationality are left unconfirmed, and when and where she was born are also unknown. Even her birth name is not believed to be real. However, she is known to have a dark past. Ada also received special training as a spy for a Chinese criminal syndicate in the underworld involved in the black market arms trade.
As an independent contractor for the syndicate, Ada worked for many external clients and organisations but often betrayed them as a means to fulfill an unknown "true purpose." One of her known clients was Derek C. Simmons, a high-ranking U.S. government official and leader of the secret organisation The Family. Simmons appreciated her as an excellent spy and imposed many orders on her for his own ideals and ambitions. He harbored a distorted attachment and love for her and thought they were a perfect partnership due to the genius characteristics they both shared. This would, however, prove to be his eventual undoing.