Variety has reported that Katrina will be reprising her role as Nyssa Al Ghul for a single episode on Arrow later this season. She will be appearing in the 16th episode, entitled The Thanatos Guild. Last we saw Nyssa was on the Lian Yu island in the Season 5 finale.
“In an unforgettable episode that will change ‘Arrow’ forever, Katrina Law returns as the Daughter of the Demon, Nyssa Al Ghul,” executive producers Wendy Mericle and Marc Guggenheim said. “Nyssa comes to Star City to warn of an impending danger that will threaten everything we know and love.”