Hawaii Five-0‘s season-opening redo of the original series’ pilot will reveal a new — and now vexing — bit of McGarrett’s romantic past.

TVLine has learned that Mistresses alum Rochelle Aytes has been cast on the CBS procedural in the recurring role of Greer, a sharp, smart and calculating CIA operative who was once romantically involved with McGarrett. Now, though, Greer is described as “dangerous and not to be trusted.”

Aytes will make her debut in the Season 9 premiere (airing Friday, Sept. 28), which as a means of commemorating the franchise’s 50th anniversary will offer its own take on the original Five-O‘s two-part pilot, which was titled “Cocoon.”

“A character named Greer was introduced in that first episode, and she had a relationship with McGarrett ‘back in the day,’ when he was in uniform,” showrunner Peter M. Lenkov told TVLine as part of our in-depth Fall Preview Q&A. As portrayed by Aytes on today’s Five-0, “She’s going to be a Big Bad in the first couple of episodes.” TV's Big Cast Changes (2018-2019)

In addition to her run on ABC’s Mistresses, Aytes’ TV credits include Designated Survivor, Criminal Minds, The Forgotten and Drive.

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