A longtime guest star who appeared in the occasional film, actor Robert Knepper finally broke through as a villain television audiences loved to hate, playing inmate and sexual predator Theodore "T-Bag" Bagwell on the hit series, "Prison Break" (Fox, 2005-09). Prior to that breakout performance, Knepper spent a solid two decades playing small roles on television, starting with transsexual Georgia Buckner on "L.A. Law" (NBC, 1986-1994), while also appearing in features like "D.O.A." (1988), "Renegades" (1989) and "Young Guns II" (1990). He upped his profile in smaller indies like Allison Anders' "Gas Food Lodging" (1992) and Woody Allen's "Everybody Says I Love You" (1996), before making memorable impressions with guest spots on "The West Wing" (NBC, 1999-2006) and "La Femme Nikita" (USA Network, 1997-2001). But it was "Prison Break" that allowed Knepper to finally receive the attention he deserved, which led to more substantial feature roles in "Good Night, and Good Luck" (2005), "Hitman" (2007) and "Transporter 3" (2008). On the small screen, he was the main villain on the fifth and final season of "Heroes" (NBC, 2006-2010), before resuming a steady string of guest appearances on major TV shows that increased his visibility and allowed him to display his talents in a wide array of roles.