Lian Xing is a special operations field agent who is the former second-in-command to Gabriel Logan in the IPCA and former operative working in the shadowy Agency under Edward Benton. Lian is Gabe's closest ally throughout the entire series, serving as either his combat teammate or tactical advisor via radio.
Born in Kashi, China sometime in the 1970's, Lian served as an operative for the Chinese Secret Service (MSS) in soviet-occupied Afghanistan during the late 1980s, where she was assigned with gathering evidence of soviet commander Uri Gregorov's troop movements. Within the city, she ran straight into a Soviet ambush but was saved by Gabe. She had then agreed to assist Gabe in getting his truckload of arms to the rebels by making a distraction.
Chinese intel had supplied Lian with information that the soviets have developed a prototype weapon that could penetrate solid objects. She eventually got her hands on that weapon and neutralized a key number of Soviet snipers in the area. Having photographed Gregorov's area charts and blown up the underground munitions depots, Lian was extracted by chopper out of Kabul. During the chase for Erich Rhoemer in Costa Rica, Lian infiltrated Rhoemer's Labs in the Aztec Ruins. She had found out that Rhoemer's group had kidnapped a number of world renowned scientists and medical technicians to work in his labs and was ordered by Benton to get the kidnapped personnel out of there alive, via a chopper at the Eastern Temple. She was also ordered to retrieve a number of plant materials the scientists were synthesizing, as well as a synthetic computer model of the virus itself.
Lian was Gabe's radio backup throughout the first several missions, but is kidnapped by Rhoemer's men in Kazakhstan and made one of the test subjects for the virus. In Ukraine, Phagan leads Gabe to her cell, as a condition of letting him free. She reveals that the vaccine he carried, supplied by Thomas Markinson, was ineffective, and Lian's analysis later showed it to be a chemical used in lethal injections. Lian accompianes Gabe and an temporarily allied Mara Aramov to the Pharcom Warehouses in Kazakhstan, Rhomer's final safehouse. At the conclusion of the operation, she ponders to Gabe if they'll ever know the connection between Rhomer, Markinson and Phagan.
An Agency commando squad arrives in Kazhkstan, and succeds in capturing Lian. She is taken to McKenzie AFB in Colorado, where the Agency tried to extract her plasma for the incubating virus. She manages to escape and commandeer a helicopter to aid Logan. As the effects of Syphon Filter grew, she was unable to help and nearly died until Gabe returned with the vaccine from New York City. Lian would then support Gabe through the trials orchestrated by conspirator Vincent Hadden, and afterwards she became second in command of the newly reformed Agency.
She accompanied Logan on several searches related to the Omega Strain outbreaks, diverting to track other criminals that tried to obtain the virus. Her first significant appearance was in Uganda, where she investigated an Ebola outbreak with Gabe. He expresses his obsession to her at that point and feels that he needs to stop Mara Aramov.
Lian is later a playable character in the bonus mission, Kyrgysztan. She hears news of a bio-weapons container being sold from a warlord in Tash, Kumyr, Askar Saydahmat, to the North Koreans. The latter sends Sok-ju Yang to facilitate the transaction, but Lian kills Samaev, Saydahmat's henchman, and disguises herself as a concubine to fool the North Korean agent. Giving Yang the bio-weapons case, Lian eliminates him to re-acquire the container, and then poisons Saydahmat's water chalice. She also kills a seemingly innocent Yemeni terrorist, Zayed al Dhahiri.
She later plays a larger role, having worked undercover in Murukawa Industries. Assaulting the Murukawa headquarters with Gina Hunter and the IPCA agents, the helicopter is hit by a SMAW missile, but Gina lands safely and the agents are deployed. Lian planted a camera inside Murukawa's suite, which shows that Mara Aramov visited the Japanese, and convinced him to commit suicide in order for him to stay silent. Later, she meets the agents on the rooftop and protects the helicopter before extraction.
Some time earlier, Lian and Imani flipped a coin to see who would follow another North Korean agent, Yong-jun Kim. Imani Grey lost and she had to get on a flight to trail the man. Upon flying back to base, Lian learns that Imani's flight went down inside the Myanmar jungle, and guilt-striken, she brings the IPCA agents to the crash site with her. Injured due to the helicopter attack sustained previously, she stays at the boat while the agents kill the terrorists responsible for destroying the jet and recover Imani Grey's remains. They also find evidence that the plane crash was due not to weather factors, but a missile brought it down, and recover documents proving this.
After Logan later shows his reluctance to obey the Presidential administration, he decides to investigate Niculescu's business despite Birchim's orders telling him to avoid Mihai Niculescu. Lian was instrumental to counter his decision, but Logan overrided her, telling her that 'didn't give a damn about Ivankov', because he 'wanted Niculescu'. The mission seemed to fail at first, but a paper trail directed Gabe to Niculescu's villa estate, where he found Mara and the missing pieces. Lian later apologised to Gabe, saying that he knew better, but Logan told her that she was right and they only got lucky.
Agency personnel reported seeing visible concern of the behavior displayed by Logan as he became more determined to stop the Syphon Filter conspiracy. Lian continued to aid Gabe after an Agency suspension by Alex Birchim, and together they brought down the final threats.
Lian joined Gabe when a paramilitary group targeted the Alaskan oil refinery. She was a playable character in an operation to sabotage Red Section and ground their plane after she found out that they were flying with unauthorised air codes under NORAD's nose. She eventually provided Gabe with covering fire when he tried to diffuse the bombs planted around the refinery. Both were successful in their mission which resulted in Black King, a Red Section leader, getting killed, but the hostages committed suicide.
Gabe later brings Lian on a mission to destroy Red Section and rescue Blake Hargrove. The girl is Addison Hargrove's daughter, and it is later revealed Gabe's daughter as well. Lian rescues Blake from drowning, but the girl runs off and Lian loses her. She destroys the Red Section computer terminals, and helps Gabe by killing a guard who patrolled a doorway. Gabe eventually has Lian escort Blake to safety after rescuing the girl from being killed.
Lian was forced to return to Shen when his X-Z-2 device was stolen by terrorists, but Shen eventually killed himself rather than risk her life and his own. With the mission complete, Lian learned that Gabe planned on retiring, but Trinidad appeared again and targeted her. Gabe blocked the bullets meant for Lian, and in the exchange of bullets, Trinidad shot Gabe four times while Logan fired two shots at her, apparently killing her. Lian is last seen attempting to revive Gabe.
- The first Syphon Filter instruction manual lists a "fake background", as the information was "Agency-forged" following her recruitment. She is listed as being born in California and having obtained several degrees from U.S. Universities. This is impossible, due to the fact that she was still a Chinese MSS Agent until 1995(or 1996, see below point regarding conflicting dates).
- This fact is confirmed in the Syphon Filter 2 manual in the following quotation - "Originally an agent for the Chinese MSS, she was recruited in 1996 by the Agency and given a new identity as an American citizen including fake biographical information".
- There are some conflicting dates in the instruction manuals regarding Lian's background. Excluding the first Syphon Filter's manual, Syphon Filter 2 and 3 list her as being in the Agency from 1995-2000 (though SF2 says "Present", as they were still Operatives at the time). However, both Backgrounds describe her as being recruited in 1996 rather than 1995.
- In addition, both books list her as being in the Chinese MSS starting in 1989. However, she was already on a mission for the MSS as early as 1987 when she first met Gabe in Kabul, Afghanistan. The manual from Syphon Filter: Dark Mirror states that she obtained a Government job at the age of 17, which COULD be why she was in Kabul however she states in her Testimony to Vince Hadden that she was on an assignment FOR the MSS.
- Lian is the only lead protagonist with over three different voice actors. She is also one of several characters to have a different voice actor since the first game, with Mara Aramov holding the record of a different voice actor for each of her appearances in the series. The same could be said for Vince Hadden, whose voice changed in each title of the original trilogy.
- Unlike Gabe, whose hair often changes between titles, Lian has always had her hair parted in the center and cut mid-length down to her jaw. In the second game it appears however that some strands are divided along the center of her forehead.
- Lian's missions are mostly based around stealth, though can develop into action sequences depending on the level. Gabe on the other hand is given more action sequences, with only some stealth.
- Lian, with the exception of Teresa (as she was not present in the first title), is the only female character to live through all of the games.
- In SF3's multiplayer game, Lian tends to taunt her enemy with her sharp tone:
- " Get on your knees and beg! "
- " You don't want to make me angry. "
- " What do you aiming at? "
- " Are we having fun yet? "
- " Surrender youself! "
- " How dare you shoot a lady! "
- " How many times do I have to kill you? "
- " You're going down! "
- " Oh, I'm so scared! " (sarcasm)
- Lian is also the only lead protagonist out of the original four who is not potentially dead (where as the other three are left unknown, due to a cliffhanger ending in the most recent title).