Tzi Ma as Cheng Zhi
|First appearance||Day 4 – Episode 21|
|Last appearance||Day 9 – Episode 12|
|Portrayed by||Tzi Ma|
|Days||4, 5, 6, 9|
Cheng Zhi (Simplified Chinese: 程志) (Pinyin: Chéng zhì) is a fictional character played by Tzi Ma on the television series 24. He is a former senior official of the security apparatus of China, now working for himself, and an enemy of Jack Bauer. At the end of Day 6, Jack badly scars and captures Cheng during an assault, but Cheng dramatically resurfaces during the events of Day 9 in London.
Cheng first appeared in the fourth season. His position was that of Head of Security at the Chinese Consulate in Los Angeles. Due to a nuclear threat against the United States, a strike force led by Jack Bauer raided the Consulate to capture a suspect, and in the process the Chinese Consul was killed. Cheng felt the incident that occurred violated all diplomatic rules and the sovereignty of the Consulate, and upon investigation learned that Bauer was responsible. In order to avoid standing trial in China, Jack faked his death.
Cheng re-appeared in the fifth season, apparently learning that Bauer was indeed alive, and the season ended with him successfully kidnapping Jack and transporting him to China.
In the sixth season, Cheng returns with Jack to Los Angeles, where he gives Jack back to CTU, commenting that Jack had not spoken a word in two years. When the nuclear crisis was resolved Cheng resurfaced and is seen holding Audrey Raines, who was earlier believed to be deceased. He demanded a component of one of the nuclear weapons in exchange for her safety. Jack is arrested while trying to obtain the component, however gets the blessing of the President after speaking to him. He assures President Wayne Palmer that he will destroy the device after learning that Audrey is safe. As Jack is on his way to Cheng with the component, Vice President Noah Daniels shoots down the mission because he is now in power after the latest health situation of Palmer. Jack is able to get Mike Doyle out of the car at gunpoint, and leaves to meet Cheng and Audrey.
When Cheng dictates the meeting point for the exchange, Jack refuses. They settle on a neutral area. When Cheng arrives, Jack exchanges the component for Audrey. He tells her to walk 100 yards past the bridge, which is visible from the building. As Audrey is walking, Doyle and other CTU agents engage in a fire fight. At this time, Cheng escapes with the component. At the end of the episode, it is revealed that Audrey has somehow been brainwashed by the Chinese.
When Cheng attempts to gain information from the component, access is denied. He needs to pass through the override, but needs the help of CTU. He sends a man named Zhou and his team on a mission to CTU, which claims the life of Milo Pressman, in order to retrieve Jack's nephew, Josh Bauer, for Jack's father, Phillip Bauer. In exchange, the elder Bauer is fixing the sub-circuit board for Cheng.
The plan does not go as he expected though. Jack Bauer and a CTU tactical team surprise Cheng and his men as they leave to meet Phillip Bauer. During the exchange, most of Cheng's men were killed and he himself was nearly captured by Jack. Cheng is only able to escape because Jack chose to rescue Josh instead of going after him.
Not long after, Phillip is furious to find out what happened. He refuses to give the circuit board back to Cheng. The two get into a verbal argument. In the end, they threaten each other and Phillip is trying to give the board to the United States Government in exchange for his grandson.
In the season finale, Cheng has resumed a working relationship with Phillip. Cheng arranges for a Chinese submarine to retrieve Phillip and Josh from the abandoned oil rig where they had set up a base. However, before they can do so, an airstrike destroys the platform. Phillip is presumably killed, the circuit board is destroyed, and Cheng is taken into custody. As of the end of the finale, Cheng is told that he will be transferred into federal custody. Cheng merely replies, "My people will not abandon me like you abandoned Jack Bauer."
Cheng reappears during the events of Day 9 in London. He is shown retrieving the override device used by Margot Al-Harazi to hack the U.S. military drones from Adrian Cross after murdering the other members of Open Cell. After retrieving the device, Cheng forces Chloe O'Brian to alter the device for his own purposes and shoots Cross in the head after she was finished. Then, Cheng uses the device to order a U.S. Navy nuclear submarine to sink a Chinese aircraft carrier.
It is revealed that Cheng was working with Russia in an attempt to start a war between the U.S. and China. Cheng and his men are instructed to go to a ship to escape the country by their Russian contact. Shortly after arriving, they are eventually tracked down to a ship by Jack, Belcheck and Chloe. After learning of Audrey's death from Kate Morgan, Jack in a fit of rage slaughters all of Cheng's henchmen before finding Cheng himself and engaging him in hand-to-hand combat. Jack gains the upper hand when he breaks Cheng's arm and grabs a katana hanging on the wall of the ship, placing it to Cheng's neck and forcing him to identify himself as the CIA and President Heller look on. After his facial and vocal recognition match with files from six years ago, the video of his identification is sent to the Chinese president in an attempt to convince China to stop the attack on U.S. naval forces in Okinawa. After confirmation Cheng was identified, Jack beheads Cheng with the katana to avenge Audrey's murder. 
- Writer: Joel Surnow Director: Brad Turner (2007-04-23). "12:00pm-1:00am". 24. Season 6. Episode 139.
- Writer: Manny Coto Director: Bryan Spicer (2007-05-07). "2:00am-3:00am". 24. Season 6. Episode 141.
- Writer: Howard Gordon Director: Bryan Spicer (2007-05-14). "3:00am-4:00am". 24. Season 6. Episode 142.
- Writer: Joel Surnow Director: Brad Turner (2007-05-21). "4:00am-5:00am". 24. Season 6. Episode 143.
- Writer: Robert Cochran Director: Brad Turner (2007-05-21). "5:00am-6:00am". 24. Season 6. Episode 144.
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