According to a report from TVGuide.com, Law’s character of Nyssa will arrive in Starling City in the 13th episode of the current Season 2. The episode’s title, “Heir to the Demon,” seems to refer directly to Nyssa — “Ra’s al Ghul” means “head of the demon” in Arabic.
So far on “Arrow,” Ra’s al Ghul has been nothing but a shady figure referred to by the Black Canary/Sara Lance (Caity Lotz). Assassins from al Ghul’s League of Assassins showed up in Starling City in order to either kill or return Sara to the head of the organization. “Arrow” has not yet announced any plans to bring al Ghul himself to the show.
Nyssa al Ghul does appear in DC Comics as a member of the League. If this character follows the standard procedure for “Arrow,” she will have a slightly different role to play in the TV version.
“Arrow” airs Wednesdays at 9 p.m. on The CW.