Profile: Julian Sark
Case Details: Has assumed co-leadership of the North American division of The Covenant, along with Lauren Reed.
Date of Birth: Unknown
Place of Birth: Possibly Galway, Ireland
Height: 5'11"
Weight: 175
Sex: M
Age: Unknown; estimated at mid to late 20's.
Grew Up: England, where he went to school at a young age.
Race: Caucasian
Languages: English, French
Education: Unknown
Employment: Once worked for "The Man" ie. Irina Derevko. Routinely shifts alliances.
Personal Details: Ordered Lauren Reed to assassinate Adrian Lazarey, his father, after he assisted Sydney Bristow in the search for the Rambaldi Cube. Engaged in an affair with Lauren Reed, CIA Agent Michael Vaughn's wife. Invested his inheritance, estimated at $800 million, in The Covenant.
Miscellaneous: Assassinated Quan Li, leader of SD-6 rival FTL. Killed Ilyich Ivankov, head of K-Directorate.
Training/Special Skills: Unknown, but consider him highly dangerous

Julian Sark, played by David Anders, was the co-leader of the North American branch of The Covenant on the television series, Alias.

Much is unknown about Sark. He spent most of his youth in England, although it is believed that he was born in Galway, Ireland. He is apparently very wealthy, partly as a result of an inheritance from his Romanov-descended father, Andrian Lazarey.

Sark is the dashing, young bad guy in Alias. He routinely changes his alliances, and he alone knows where his true allegiance is. His smarmy attitude often reflects his ability to foil plans for his capture; however, he has been imprisoned by the CIA twice so far, escaping both times. He has previously worked for and with both Arvin Sloane and Irina Derevko, as well as several other nefarious people and organizations. He and NSC turncoat Lauren Reed were also co-leaders of the North American branch of The Covenant.

Source: ABC's Alias & Wikipedia.