He was notorious for changing alliances, offering his services to anyone who paid enough money (or agreed to let him stay alive) - even the US government. As stated by Anna Espinosa, Sark was a man so ruthless in his shifting allegiances that he killed his own father.
He was skilled in evading capture, managing to stay active years after the destruction of APO despite two previous CIA imprisonments.
Little is known about Sark's background. He spent most of his youth in the United Kingdom, although a voice analysis revealed he also spent a lot of time in Galway, Ireland. He is the heir to a vast fortune from his Romanov-descended father, Andrian Lazarey.
Sark initially operated as an agent of a criminal organization headed by a figure known only as "The Man" (believed at first to be Alexander Khasinau , but later revealed to be Irina Derevko). He leads a strike team against FTL Headquarters and killed the head of FTL, Quan Li, in broad daylight, just outside FTL's front door. The attack coincided precisely with McKenas Cole's unsuccessful assault on SD-6 and was designed to retrieve an unknown Rambaldi artifact (Cole's was to obtain an ampule of unknown liquid).
SD-6 learned of a scheduled meeting between with K-Directorate to discuss the sharing of Rambaldi technology; Sydney and Dixon were tasked with eavesdropping on the meeting (The Coup).
Sark offered to transfer $100 million to K-Directorate's Cayman Islands account in exchange for the Rambaldi manuscript (which included Page 47) (Page 47). The offer was rejected and Sark assassinated Ilyich Ivankov, leader of K-Directorate. The new leader of K-Directorate, Lavro Kessar, accepted the offer. Sydney, who was dangling outside the window, was spotted and a firefight ensued; Sark slipped away. He was next seen in Tunisia, trying to retrieve the Rambaldi manuscript, but Sydney got to it first.
Sark traveled to Denpasar to buy a second ampule of Rambaldi liquid in order to expose a Rambaldi document (possibly the artifact retrieved from FTL). Unknown to him, the buy was a sting operation set up by Sydney and Vaughn (The Solution). It was disrupted by Dixon and other SD-6 agents. Sark tried to flee, but was captured by Vaughn. When Vaughn abandoned Sark to rescue Sydney, SD-6 recovered him (Rendezvous).
While in SD-6 custody, he agreed to lead SD-6 to Khasinau so they can recover the Rambaldi document. Sydney and Dixon were tasked to retrieve the document and replace it with a forgery. Vaughn instructed Sydney to switch out the document with a counterfeit, but she unable because she spotted Will Tippin. Sark again escaped, but was tracked by Sloane (who had laced Sark's wine with a radioactive isotope in order to track him via satellite). When Sark realized this, he had a full blood transfusion in Geneva. Sark returned to Los Angeles and kidnapped Will Tippin from a CIA safehouse. To secure Will's release, Jack stole the ampule from the CIA and Sydney stole the document from SD-6. They exposed the page and realized that it was "The Circumference" (instructions on how to use the Mueller device). Jack traveled to Taipei for the exchange and then Sark vanished (Almost Thirty Years).
Sark initially assumed control of Irina's assets, but later allied with SD-6 (Sloane) in a secret collaboration to provide Sydney with the location of "Server 47" (The Counteragent). On the server was enough intelligence to destroy The Alliance of Twelve and all the SD cells, however,
no Rambaldi artifacts were found at any of the SD sites. After the fall of SD-6, Sark continued to work with Sloane. He co-ordinated the murder and replacement of Sydney's friend, Francie Calfo, by Allison Doren, who had been transformed by Project Helix into Francie's genetic duplicate (Phase One). He also kidnapped the wife and son of mathematician Dr. Neil Caplan in order to coerce Caplan into assembling the artifacts into a neutron bomb (A Free Agent). At the end of the season, Sark was taken into CIA custody (The Telling).
Sark became the chief financier of The Covenant.
During the two-year time that Sydney was brainwashed as Julia Thorne, she was sent to assassinate Andrian Lazarey (Sark's father). His apparent death left an $800 million gold bullion inheritance for Sark. The Covenant set up an exchange for Sark's release from CIA custody; he was to be traded for captured CIA agents (Succession). The Covenant double-crosses the CIA at the exchange. A man named Ushek San'ko, leader of The Covenant, says that Sark killed his brother, and demands his $800 million inheritance.
Sark carried out several missions for the Covenant, sometimes with the aid of Lauren Reed, Vaughn's wife - a double agent positioned within the NSC. He goes on at least one mission with Allison Doren, whom he claims to love despite her being stuck as a doppelganger of Francie (The Nemesis). Doren is ultimately killed by Tippin in the course of the mission.
Sark also eventually tracked down what happened to his father and he uncovered the truth about Julia Thorne. He discovered his father was actually alive, having faked his death in order to pass on Sark's inheritance to him. In the events that follow, Doren is killed by Will during a struggle (Remnants). Later, he sent Lauren to assassinate his father, this time for real (Full Disclosure).
Sark and Reed conspired to assassinate the leaders of the six Covenant cells in an attempt to take control of the organization and eventually also became lovers. After the assassinations, McKenas Cole became Sark and Lauren's second-in-command (After Six). Once again, they allied with Arvin Sloane to obtain the Rambaldi equation channeled by Nadia Santos ("The Passenger"), however, they were unsuccessful. Reed carried out a mission disguised as Sydney in order to get the equation and bomb the CIA headquarters while Sark monitored her. She escaped, but he was captured (Façade).
When the CIA picked up an aircraft in the Ural Mountains deploying the bio-weapon against a prison, they noticed Sark was extracting the sole survivor - Kazari Bomani, the largest arms dealer in Africa. However, when Bomani later prepared to kill Lauren, Sark shot and killed him (The Frame). Sark then kidnapped and tortured Vaughn in attempt to get information about the The Passenger's location. When Lauren appeared, she was obviously disturbed by Vaughn's condition and helped him escape (Blood Ties). He is again, captured and imprisoned by the CIA while Lauren escaped (Legacy).
During his second CIA-imposed imprisonment, Marshall suggested they enlist Sark's help to track down terrorist Anna Espinosa. He initially refused. When Vaughn visited him in his federal prison cell, Sark asked if Lauren was killed because of her espionage or her infidelity and Vaughn punched him.
When Sark refused to answer any more questions, Vaughn had him shipped to Alder Penitentiary, where he was to spend every day in dark cell, in solitary confinement (Echoes). Sark was next brought before Sloane, who again asked for his help. This time he agreed, but only on the condition that he was shown proof of Lauren's death (as he claimed she was the woman he loved). After he saw her body in a secret CIA mortuary, Sark realized that it was Vaughn who killed her.
During the mission, Sydney posed as Lauren. She shared a passionate kiss with Sark in order to impress their buyer and sell their cover. Espinosa suddenly appeared and helped Sark escape. She claimed her original buyer did not offer enough money for her chemical bomb and proposed she and Sark collaborate to sell it. She also helped remove the explosive tracking device that CIA has planted into Sark's neck. He agreed to help her, but eventually turned on Anna, trapping her in an elevator and thus, leaving her for Sydney to kill or capture. While Anna fought Sydney and was ultimately taken into CIA custody, Sark took advantage of the situation and disappeared (A Man Of His Word).
With the death of Covenant leader Elena Derevko and the resulting apparent fall of The Covenant, Sark went freelance. He worked on behalf of a Sudanese warlord to obtain a weapon of mass destruction. He met new APO recruit, Rachel Gibson,
in a bar and they go back to his room - unaware that they each intend to intercept the transmission about the weapon. She found an airline ticket indicating Sark is headed to the Bahamas next. They finished their respective work and went their separate ways. Once home, Rachel discovered Sark's true identity via video footage and informed Sydney where to find him. They brokered a deal with Sark to help recover the kidnapped Jack and Elizabeth. During the mission, Rachel saved Sark's life and he, in turn, decided to refuse payment for his services. This move left Rachel intrigued (Bob).
Later, Sloane sent Sark a secret message, presumably to secure his services for work with Anna Espinosa (in reality, it was Sydney impersonating the Anna/Sydney doppelganger) (I See Dead People). Sark engineered for them to be taken into custody in an Italian prison in order to secure a Rambaldi amulet from an elderly man known only as "The Rose" (No Hard Feelings).
Sark later teamed with Sloane and Kelly Peyton to get The Horizon, the final Rambaldi artifact needed by Sloane, from Irina in exchange for two missiles. As part of their plan, he went undercover in Prophet Five (Reprisal).
After he planted a bomb that destroyed APO headquarters (and killed Thomas Grace), Sark accompanied Sloane to Mongolia to excavate the tomb of Milo Rambaldi. He became involved in a stand-off with Vaughn, Jack Bristow, and Sloane's other operatives. In the ensuing gun battle within Rambaldi's tomb, Sark retrieved the Horizon and returned it to Irina in Hong Kong. On Irina's orders, Sark prepared to launch missiles at Washington, D.C. and London, but he was captured and shot by Vaughn. In exchange for his freedom, he gave Vaughn the abort codes. After the missiles were stopped, Vaughn let a wounded Sark free (All The Time In The World).
Sark was still active years after Sydney and Vaughn retired. Dixon came to their home and requested they help him track down Sark, who had stolen a hard drive that contained classified information. Sydney joked Vaughn should have stopped Sark when he had the chance (All The Time In The World).
- Andrian Lazarey - father (deceased)
- Sark was a connoisseur of fine wine with a preference for '82 Chateau Petrus (Rendezvous).
- He is the only recurring criminal to remain active at the end of the series. (See character appearances for more information).
- Originally, J.J Abrams intended for Sark to appear in only a few episodes.