As the mob-connected Las Vegas undersheriff Jeffrey McKeen on "CSI: Crime Scene Investigation" (CBS, 2000-2015), Conor O'Farrell thwarted the efforts of the investigators across several seasons until he was finally put behind bars. While his portrayal of McKeen was one of his best-known roles, O'Farrell appeared on numerous popular television shows starting in 1989, as well as a handful of movies, including a large role alongside Kevin Bacon in "Stir of Echoes" (1999). O'Farrell was born in Riverside County, California and began taking acting classes in his early 20s in Los Angeles. After three years, he moved to New York where he continued to study acting. Before long he was performing on stage in plays such as "Death of a Salesman," "The Glass Menagerie" and "Tartuffe." He landed his first TV role on the action drama "Hunter" (NBC, 1984-1991), and subsequently began working regularly on TV. In 1996, he appeared in his first film role, "The Trigger Effect" (1996), and that same year he became a regular cast member on "Dark Skies" (NBC, 1996-1997). Although "Dark Skies" was cancelled before finishing its first season, O'Farrell's work on TV continued with regular guest spots on "Party of Five" (Fox, 1994-2000), "Ally McBeal" (Fox, 1997-2002) and "Star Trek: Enterprise" (UPN, 2001-2005). He also appeared on the TV miniseries "From the Earth to the Moon" (HBO, 1998), and had a major role in "Stir of Echoes" (1999) starring Kevin Bacon. Besides appearing in several episodes of "Medium" (NBC, 2005-09, CBS, 2009-11) "Lie to Me" (Fox 2009-2011), "True Blood" (HBO, 2008-2014), and the miniseries "The Pacific" (HBO, 2010), O'Farrell played the corrupt mob boss Jeffrey McKeen on "CSI: Crime Scene Investigation" across several seasons. He also had a small role in the feature film "The Lincoln Lawyer" (2011) with Matthew McConaughey and co-starred in short-lived police drama "Gang-Related" (Fox 2014) and the dysfunctional family comedy-drama "See You In Valhalla" (2015).