'Grey's Anatomy': Kate Walsh Returning for Season 18

The actress will reprise her role as Dr. Addison Montgomery in multiple episodes.

She's back! Grey's Anatomy will welcome back Kate Walsh for the upcoming 18th season, it was revealed Thursday in a special video message by Walsh.

The actress, who played Dr. Addison Montgomery on Grey's before headlining the Private Practice spinoff, will appear in multiple episodes, ET can confirm.

"Well, well, well, would you look who it is? That's right, my loves. Dr. Addison Montgomery is coming back to Grey Sloan Memorial Hospital," Walsh says in the video. "I'm so excited to be coming home again, joining Shonda [Rhimes], Ellen [Pompeo] and the rest of the incredible cast. This season -- 18! -- just wait until you see what she has in store for you."

While it's unclear when or in what context Walsh's first appearance will be, she hinted at her character's "grand return." 

Watch the announcement below.

Walsh first made her debut as Addison in dramatic fashion in the final moments of the season 1 finale of Grey's in 2005, when her surprise arrival in Seattle complicated her then-husband Derek Shepherd's romantic relationship with then-intern Meredith Grey. Walsh remained a series regular for seasons 2 and 3 before transitioning to lead Private Practice, which ran for six seasons until 2013.

The actress' reprisal comes a few weeks after Kate Burton's return as Meredith's late mother, Ellis Grey, was announced. Since season 17, Grey's has seen a flurry of familiar faces pop back in following last year's appearances by former cast members Patrick Dempsey, T.R. Knight, Chyler Leigh, Sarah Drew and Eric Dane.

Grey's Anatomy premieres Thursday, Sept. 30 on ABC. For more, watch below.

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