Street Fighter: The Legend of Chun-Li

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Chun-Li moves from San Francisco to Hong Kong with her family. While practicing to be a concert pianist, she learns Wushu from her father, businessman Xiang. For a while, her life is perfect until one night, Xiang is attacked and abducted by M. Bison's henchmen in front of Chun-Li.
Years later, Chun-Li grows up and becomes a talented pianist. At the end of her concert, she receives a mysterious scroll written in ancient Chinese text. Shortly after, she loses her mother to cancer. Meanwhile, at Shadaloo headquarters in Bangkok, Thailand, Bison announces his complete control of the organization before he has the other shareholders executed by one of his henchmen, Vega. It is also revealed that Xiang is still alive and working for Bison.
The next day, Royal Thai Police detective Maya Sunee meets Interpol agent Charlie Nash, when both are called to investigate the murder of several crime syndicate families in Bangkok. Nash informs Maya that the Shadaloo perpetrated these crimes. Back in Hong Kong, an elderly woman translates Chun-Li's scroll and tells her to travel to Bangkok and find a man named Gen. Chun-Li then leaves her home and travels to Bangkok, living homeless and searching for Gen for several days. A fight with local gangsters one night leaves her exhausted and unconscious, and Gen appears and brings her to his home.
Gen informs her that he was once comrades with Bison and he knows how to find her father, and for the next few days, he teaches her his style of martial arts. Chun-Li also learns more about Bison, who is operating Shadaloo publicly, and is holding the families of property owners hostage in order to force them to sign their property over to him. While spying on Bison's henchman Balrog, she overhears that a property owner is asked to hand over the rights to a docking harbor, allowing the shipment of the "White Rose".
Later that night, Chun-Li confronts Cantana, one of Bison's secretaries, in a nightclub. She obtains information on the location of the White Rose before escaping from Shadaloo's thugs and Nash and Maya. As a result of this incident, Cantana is used as a punching bag by Bison the next day and killed.
Gen tells Chun-Li more of Bison's origin. The son of Irish missionaries, Bison grew up an orphan and lived his entire life as a thief. Many years later, as a means of becoming completely evil, he killed his pregnant wife and transferred his conscience into their prematurely born daughter. After telling Chun-Li to go and fetch some food, Gen is attacked by Shadaloo troops before Balrog blows up his house. Chun-Li runs off when she is attacked by Vega, whom she soundly defeats and leaves hanging by the side of a building.
The next day, Chun-Li interrogates a harbor employee into telling her the arrival time of the White Rose. She returns to the shipping yard that night, only to fall into a trap as Bison and his soldiers capture her. Tied up and brought into an undisclosed house, she is reunited with Xiang, only for Bison to kill him by breaking his neck. After Bison and Balrog leave the house, Chun-Li uses her skills to defeat the guards and escape. During the escape, she is shot in the arm by Balrog while trying to protect a child. Angered Thai locals then pelt Balrog and other Shadaloo henchmen with fruits, food, and other merchandise. Chun-Li is reunited with Gen, who heals her wounds and continues with her training.
Despite being taken off the assignment, Nash is secretly asked by Chun-Li to back her up in taking down Bison. Nash and Chun-Li, along with Maya and her SWAT team, arrive at the shipping yard, where they engage in a shootout with Shadaloo forces. Maya is wounded in the shootout, but her SWAT team manages to dwindle Shadaloo's numbers. Meanwhile, Chun-Li enters a ship and meets a girl who speaks Russian asking for her father before leaving her to continue her search for Bison. In another part of the ship, Gen faces off against Balrog, ultimately impaling him with a liquid nitrogen pipe. Bison takes the girl, who is revealed to be his daughter Rose, and flees the scene by helicopter.
Chun-Li, Gen, Nash and a SWAT officer arrive at Bison's headquarters, where Nash and the officer take Rose out to safety while Chun-Li and Gen face Bison. After a long battle, Chun-Li hits Bison with a bamboo pole and drops sandbags on him, stunning him. She then charges up a Kikoken and shoots it at him, knocking him off the scaffolding before she jumps and twists his neck with her legs. Nash tells Chun-Li to leave the scene as Thai police arrive.
Chun-Li returns to her home in Hong Kong and settles down when Gen pays her a visit. He shows her a newspaper ad for an upcoming Street Fighter tournament, telling her that a Japanese fighter named Ryu might be a recruit for their cause. She declines the offer, telling him she is home for now.

Question: What is Nash asked to do ?
Answer: To help Chun Li take down Bison.