Hawaii Five-0 is looking to the past for its latest villain.

Per TV Line, Rochelle Aytes has been cast as Greer, a CIA operative who was once romantically linked to McGarrett.

More ominously, she is now described as "dangerous and not to be trusted."

Has she always been a villain, or will big change have been part of the reason for her becoming a darker character?

It's certainly exciting that we're going to get more details on McGarrett's past because he's one of the best characters on the CBS drama.

Greer will first appear on the season premiere and will then recur throughout Hawaii Five-0 Season 9.

Hawaii Five-0 Season 9 Episode 1 will pay homage to the original series' two-part pilot.

It will all be part of a 50th-anniversary celebration since the franchise kicked off.

Aytes has also appeared on Mistresses, Criminal Minds and Drive.

It was revealed just hours ago that production on the series could be shut down temporarily as a result of Hurricane Lane.

Hawaii’s Big Island, Maui, and Oahu, including Honolulu are all currently on high alert as a result of adverse weather conditions.

CBS has already shut down production on the reboot of Magnum P.I. for the next two days, but for now, Hawaii Five-0 will remain in production until the network says otherwise.

Hawaii Five-0 will remain on Fridays this fall. It remained a reliable performer last season, averaging 8.3 million viewers and a 1.0 rating among adults 18-49 in live + same day figures.

Okay, Hawaii Five-0 Fanatics!

What are your thoughts on this casting news?