CBS’ Hawaii Five-0 has set its sights on Katrina Law, adding the Arrow alum to its Season 10 cast as a series regular.

TVLine has learned that Law will play Quinn Liu, a former Staff Sergeant with Army CID who was recently demoted for insubordination. After an explosive collision with Five-0 during a case involving veterans, Quinn becomes a loyal ally to the team. Sharp-tongued in several languages, she has a deep understanding of military culture, a mysterious past and a deft ability to match wits with McGarrett (played by Alex O’Loughlin).

Oops, spoiler: McGarrett apparently didn’t get shot dead in the season finale.

“We are thrilled to have Katrina join the [cast],” says showrunner Peter M. Lenkov. “She dazzles as Quinn, the team’s newest recruit, and viewers are going to love seeing how she first encounters McGarrett and Danny (played by Scott Caan). If you know the show well, you’ll be feeling some déjà vu.”

In addition to years of intermittent appearances as Arrow‘s Nyssa al’Ghul — whom she last played in a March flash-forward episode — Law’s previous TV credits include The Oath, Sacred Lies, Training Day, Legend of the Seeker and Spartacus. She most recently was attached to TV’s latest attempt to pilot a Frankenstein-y series.

Hawaii Five-0 opens Season 10 on Friday, Sept. 27, where it will now open the night (leading into Magnum P.I. and then Blue Bloods).

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