Kingston portrays Dinah Lance, the mother of Laurel Lance (Katie Cassidy), who first appeared last season with a theory that her daughter Sara (Caity Lotz) was still alive. We now know that Sara is, in fact, alive, but will Dinah be let in on the secret?
Arrow star Stephen Amell first teased the news on Twitter. "Working with an actor for the first time today," he wrote. Executive producers Greg Berlanti and Andrew Kreisberg revealed that said actor is Kingston during a screening of the upcoming Flash episode on Monday.
Arrow airs Wednesdays at 8/7c on The CW.
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