|Seen||"Kung Fu Crabtree"|
|Status||Living, presumably to be hanged|
|Relationships||Wu Ling, sister, Yu Da, wushu master, deceased, unnamed father, deceased|
Wu Chang (aka Chin Lau) was a political reformist and martial artist on the run from China.
Wu Chang is first seen as part of a lineup of the staff of the Chinese restaurant where Chow Wei was killed. He identifies himself as Chin Lau to Sun Yang, but Sun Yang recognizes him from the photos of the alleged Boxers and tries to have him arrested. He fights off Inspector Brackenreid, Crabtree, and Constable Higgins, then escapes, stealing the two officers' nightsticks.
Later on, Wu Chang finds a message at his rooming house that tells him to meet with his martial arts master, Yu Da, back at the restaurant. He returns, only to hide quickly on the ceiling once George comes to investigate further. Wu Chang attempts to get away and is caught by George, who handcuffs himself to the fugitive.
But just as Crabtree does so, he and Wu Chang are attacked by three black clad, masked men armed with Chinese broadswords. Wu Chang is able to fight them off, utilizing his wushu and the nightsticks, which he chained together. George helps a little, and afterwards releases Wu Chang from the handcuffs, believing him to be innocent.
George then takes him to a doctor because he's been wounded. While Wu Chang's wound is stitched up by Emily Grace, Crabtree and Dr. Grace learn that the restaurant message was ruse, he's not a Boxer, and learned English from his father, who believed the future of China lay in the West.
Later on, Wu Chang and Crabtree wander through Chinatown, talking about Wu Chang's fighting skills. He identifies this as kung fu, and George asks to learn it. Wu Chang clarifies, saying kung fu is any skill that is achieved through hard work and diligence, and what he practiced was wushu, the art of defending oneself.
Crabtree begs to learn a move, and Wu Chang teaches him some wisdom ("When your opponent strikes, he only thinks about your weakness. That is his weakness.") and then how to free a hostage from an opponent. The two men bond, and George takes Wu Chang to hide in his apartment.
Wu Chang agrees to let George Crabtree do his job and prove his innocence while he remains in hiding. Wu then questions him about Dr. Grace and the nature of their relationship, as he had seen [Leslie Garland]] come for a date with Emily. George explains the full story, and Wu Chang is impressed that he's sacrificed his happiness for hers, naming him as a man of honour.
The next day, Wu Chang discovers Crabtree leading officers to the apartment and he runs away, believing George has betrayed him. Crabtree later finds him at his master's house, and confronts him about the man he killed in China, but Wu Chang states he killed the man to defend his father. Yu Da then hides the two as the same three attackers come for Wu Chang again, and defeats them even though he is blind.
Wu Chang then shares with George that his father, sister, Yu Da and himself were friends with the true emperor, who was overthrown by usurpers because he wanted to make the Chinese government into a constitutional monarchy. The Empress Dowager then set out to kill the reformists, Wu Chang's father being one of the victims. The reformists were forced to flee China, and the Empress garnered international help by labelling the fugitives as Boxers.
Crabtree takes Wu Chang to the station to try and explain things to the inspector, then the three of them return to Yu Da's house to talk to him, Wu Chang being handcuffed once more to George as part of a compromise. However, Yu Da has been murdered, and the attackers have his sister Wu Ling.
Wu Chang quickly cuts off the handcuffs and goes back to the Chinese restaurant, fighting off the attackers and freeing his Wu Ling. George and the inspector soon arrive with rifles to help out, but Mrs. Brackenreid appears and is taken hostage. George however, uses his newfound learning to save her, and the attackers are quickly apprehended, one being Sun Yang.
Afterwards, George questions him and Wu Ling about their motives for the murder. However, Crabtree realizes that Wu Ling had the motive, means, and opportunity to commit the crime, thus she had done it. But as he vocalizes his suspicions, Wu Chang is the only one who understand English out of the two of them. He realizes Crabtree is correct, and confesses to the crime to save his sister from the noose. George rails against him for admitting to a crime that he didn't commit, and Wu Chang explains his reasoning. It was better to save his sister, as when the Empress regained international favour Canada would send him back, and he would die by a thousand cuts. Also, Wu Chang reveals he killed the man in China after his father was dead, making it murder. He calls George his friend and tells him it's for the best.
Presumably, Wu Chang will be hanged for this premeditated murder.