'Arrow' season 5 cast news, spoilers: Is Talia al Ghul's introduction a prelude to Batman's?

"Arrow" season 5 is beefing up its universe with the addition of Talia al Ghul, who will be played by "Continuum" alum Lexa Doig.

Deadline reports that Doig will recur in the action crime series as the daughter of Ra's al Ghul (Matt Nable), who was introduced in season 3, and the half-sister of Nyssa al Ghul (Katrina Law), who first appeared in season 2. Talia is described as an elite warrior who "doesn't pick sides but rather creates her own." She is highly intelligent, an expert in hand-to-hand fighting, and well-trained in many weapons.

Doig will make her "Arrow" debut as Talia in episode 10 of the current season before recurring in multiple episodes. The character, Ra's al Ghul's oldest daughter, has already appeared on The CW's "Legends of Tomorrow" as a young girl. Talia is known as one of the most formidable supervillains in the DC Comics.

Prior to her casting in "Arrow" season 5, Doig appeared in the TV shows "Andromeda," "Eureka," "Supernatural" and "Saving Hope."

The introduction of the adult Talia in The CW's DC universe may have major ramifications if her story follows the one in the comic books. As DC fans know, apart from being a powerful character, Talia is an on-and-off romantic interest of Batman, whose life she saved multiple times and with whom she had a child. While Batman already appears in the DC Cinematic Universe (played by Ben Affleck) and in "Gotham" (played by David Mazouz), the people behind "Arrow" have previously confirmed that they are open to the possibility of having the Caped Crusader appear on the show as well.

Back when Ra's al Ghul was a major presence in the third season, fans had anticipated that Batman could somehow be involved in the supervillain's arc. Unfortunately, this didn't happen. But now that Talia, with whom Batman has a complicated history, is about to be introduced, fans are once again hoping that the iconic hero could finally enter the series.

"At the end of the day, it'd be so awesome to have Batman on the show," "Arrow" executive producer Marc Guggenheim told The Hollywood Reporter last year. "That'd be really cool. I don't think that will be happening anytime soon, but you never know... one day. One thing we're always saying... we ended up with a lot more DC Comics characters becoming part of the show than we had ever planned.

"Arrow" season 5 airs Wednesdays at 8 p.m. EDT on The CW.