As soon as Katie Cassidy appeared on The Flash as Black Siren/Laurel Lance of Earth-2, the idea of how Quentin (Paul Blackthorne) would react to seeing an evil version of his dead daughter came to mind. It was addressed near the end of season five of Arrow, as the two had a few scenes together. It was in those scenes and a few with Oliver (Stephen Amell) that we got the impression that there is more to the character than just evil. That there is some of what made up Earth-1 Laurel in there, too.
In a new behind-the-scenes video, Cassidy talked about returning to the show and working with Blackthorne with this new dynamic. After years of playing a relationship one way, to suddenly be a different version of a character is tough — but to play that off of a character they're supposed to love would be difficult and Cassidy brought that up to writer Marc Guggemheim. He told her to use that difficulty in the scenes.
With Cassidy back as a series regular, the show could explore the relationship between the two more — if he survives Lian Yu. Quentin has not appeared in any of the trailers for the new season, Blackthorne was not at Comic-Con this year, and the actor has been posting images from his upcoming swim with sharks on Saturday. Nothing from the Arrow set. He is one of two people that are thought to not survive the island, the other being Samantha Clayton, William's mother.
Arrow returns October 12th at 9 p.m. EST on the CW.