"Arrow" has added a major character to its already stacked season five roster: Talia al Ghul. The classic character, a long-running member of Batman's supporting cast and rogue's gallery, will be played by Lexa Doig ("Continuum," "Stargate SG-1," "The 4400") and is slated to make a big impact this season. Talia will appear in multiple episodes of season five. Doig will debut as Talia in the tenth episode of season five, an episode titled "Who Are You?" that will most likely air in December or January.

Talia is the latest member of the al Ghul family to appear on the CW show; her half-sister Nyssa al Ghul (Katrina Law) played a major part in "Arrow" seasons two through four, and their father Ra's al Ghul (Matt Nable) was a major villain in season three of the show. The upcoming "Arrow" episode will mark Talia's big debut in the CW's Arrowverse of shows; she was previously seen as a child in an episode of the time-hopping "Legends of Tomorrow" that was set years in the past. The description provided by the CW calls Talia "an elite warrior who doesn't pick sides but rather creates her own."

The better-known daughter of Ra's al Ghul, Talia al Ghul debuted in "Detective Comics" #411 in 1971. She initially served as a love interest for Batman, with most of her villainous acts coming at the request of her father Ra's al Ghul. She's been trained by the League of Assassins and is a deadly hand-to-hand combatant and is also skilled in the use of numerous weapons. She also has a child with Batman in the comics, Damian Wayne, who has taken on the mantle of Robin. More recently, Talia has become an adversary of Batman in her own right. She helped maneuver against Batman in the 2012 feature film "The Dark Knight Rises," where she was played by Marion Cotillard. Morena Baccarin currently voices Tala al Ghul in DC's line of animated features, where she was the primary antagonist of "Batman: Bad Blood."

Lexa Doig joins the cast after a lengthy stint on the television series "Continuum." She's also appeared in a DC project before, playing Dr. Christina Lamell in a 2011 episode of "Smallville." Prior to that she had roles on "Andromeda," "The 4400" and "Stargate SG-1."

Starring Stephen Amell as the Emerald Archer, "Arrow" airs Wednesdays at 8 pm ET/PT on The CW. The series also stars Emily Bett Rickards, David Ramsey, John Barrowman, Willa Holland and more.