Updated

"NCIS" is finally filling in a major missing puzzle piece about Gibbs' background.

[Spoiler alert]

The show has cast Jeri Ryan as Gibbs' (Mark Harmon) fourth ex-wife Rebecca, TVGuide.com has learned.

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Showrunner Gary Glasberg previously teased that the mystery redhead would be introduced in Season 12. "After 12 seasons there was still one ex-wife to cast opposite Gibbs and we found her in the beautiful and talented Jeri Ryan," he said in a statement. "We're all very excited to have Jeri join us for a storyline that's chock full of surprises."

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Ryan will make her debut on the show in January.

Rebecca is the only ex of Gibbs' that viewers haven't yet met. His other ex-wives — all of whom are redheads — are Shannon (Darby Stanchfield), who was murdered along with the couple's 8-year-old daughter by a Mexican drug dealer; Diane (Melinda McGraw), who drained Gibbs' bank account before leaving him and is also the ex of Agent Fornell (Joe Spano); and Stephanie (Kathleen York), who also left him.

Ryan was previously a series regular on "Star Trek: Voyager" and "Body of Proof."

Are you looking forward to meeting Rebecca?

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