Grey's Anatomy has had quite the revolving door of cast members over the years.

On Thursday, to the surprise of fans around the world, Kate Walsh confirmed she would be stepping back into the role of Dr. Addison Montgomery.

As you will probably understand, Walsh was a popular figure in the early years of the show, later going on to lead an Addison-centric spinoff in Private Practice.

That show lasted six successful seasons and wrapped in 2013, meaning that fans have been left in the lurch about what happened to the character since.

Thankfully, it's a multi-episode arc, so we're inclined to believe this will be a meaty storyline to bring the fan-favorite back into the fold.

Montgomery announced her return in a video shared on the Grey's Anatomy social channels.

"Surprise, bitch. I bet you thought you'd seen the last of me."

The actress followed up the post with another.

"It feels so good to be home again and joining Shonda, Ellen and the rest of the incredible cast on season 18 of Grey's Anatomy. Just wait till you see what she's got in store for you."

As fans responded with their excitement, Ellen Pompeo hit up the comments.

"Let's give them what they want... quality tv drama," her comment reads, to which Walsh wrote the following:

"Meredith & Addison in 2021."

Fans of the series have been gifted many returns in recent years, including Patrick Dempsey as Derek Shepherd, Chyler Leigh as Lexi, and so much more.

Grey's Anatomy Season 19, premiering Thursday, September 30, is also set to bring back Kate Burton as Ellis Grey.

Given that the character has been dead on the show for years, it could suggest Meredith will be taking a trip back to the beach-like setting we met long-dead characters on last season.

Also set to star on Season 19 is Peter Gallagher as someone who had a close association with Ellis.

Make of that what you will.

As for who won't be back:

- Jesse Williams as Jackson Avery

- Giacommo Gianniotti as DeLuca

- Greg Germann as Tom Koracick

There are also rumors that Season 19 will mark the end of the long-running series, but we've been hearing that for years.

We'll no longer believe this show is ending until ABC announces it.

It has had an impressive run, spawning multiple spinoffs, and continues to be a solid performer in the ratings.

What are your thoughts on the news?

Hit the comments below.

Remember you can watch Grey's Anatomy online right here via TV Fanatic.

Paul Dailly was an Associate Editor for TV Fanatic.Follow him on X.