Kate Walsh Says It's Been 'Completely Surreal' Returning to 'Grey's Anatomy' (Exclusive)

The former 'Grey's' and 'Private Practice' star reprises her role as Addison Montgomery in Thursday's episode.

It's Addison Montgomery day!

Kate Walsh kicks off her anticipated return to Grey's Anatomy as the beloved OB/GYN on Thursday's episode, and she shared her excitement over her multi-episode arc with ET's Nischelle Turner over Zoom on Monday evening from Australia, where she's currently residing.

"Completely surreal," Walsh said of being back on Grey's. "Like, there's no way to even articulate it. I knew it would be odd but it was so emotional, and so big and yeah, beyond, because when's the last time you've ever gone back to a job that you started 18 years ago that you left 10 years ago? You know what I'm saying? There's no infrastructure. There's no construct for it because even if you say, 'Oh, it's kind of like going home to your parents,' and you're like, 'Wait, this is my room? OK, yeah, that's right I have an airplane bed.'"

When Walsh re-emerges in the halls of Grey Sloan Memorial Hospital, she comes in to work on a complicated medical case and also to whip the new class of residents into shape. Because, as the preview hints, they've gotten a little too lax. The 54-year-old actress, who was a series regular on Grey's for seasons 2 and 3 before leading her own spinoff, Private Practice, for six seasons, hasn't stepped into Addison's high heels in nearly a decade.

"We had been talking about it for a while, [me] coming back and just having a little visit. It's such an iconic show, it was such an important show for me in my life, in my career and so [executive producer/showrunner] Krista [Vernoff] and I had been talking and trying to find a time where it was the right time for Grey's and storylines and scheduling and all of that," Walsh revealed. "And I thought, you know what? This is the right time. Also the story, the writing is so great and I mentioned this before but Jamie Denbo, who is a longtime friend of mine, wrote this first episode that I appear in and it was so great. The writing is... classic, I would say vintage Grey's. It's that fine line in making you laugh and cry hopefully."

"It was so emotional and I think it will be also for the fans. I think in every interview I've ever done in the last 10 years or whatever, it was like, 'Would you ever go back?'" she continued. "And so guess what, yes is the answer. I am doing it, I did it, so I hope that people are going to really love it. I have gotten really positive feedback from a few people behind the scenes after seeing the episode and are really excited."

Eric McCandless/ABC

Walsh also discussed the promo teasing her return episode, acknowledging that her fiery entrance was a bit of a nod to her dramatic introduction in the season 1 finale back in 2005 when Addison unexpectedly appeared and uttered the famous line to Meredith, "You must be the woman who's been screwing my husband."

"It was funny when we first did that in the Zoom table read too. It was very funny," she recalled of her updated line longtime Grey's fans would appreciate. "I was like, OK, this is awesome. It's a total wink and a nod, total kitsch moment." 

She admitted she was initially "worried" and "nervous" about her reintroduction back into the Grey's universe. "I said to Krista and the delightful and amazingly talented Chandra Wilson, who plays Bailey, who also directs a lot of the episodes now -- she directed the episode. It was like old homeschool week and I felt in such great hands. I said to her, 'It's so weird how you immediately become an actress -- 'Wait does my hair look OK? Did I do it OK?' You just become this quivering insecure person and so in that moment you just have to land it and I'm like, 'I hope it worked!'"

Walsh played coy when asked about the state of Addison and Meredith's relationship now, following a roller coaster of ups and downs. 

"I can't talk about it too much because it kind of unfolds and it's a big reveal in this episode. But I think Addison has always respected her and I think that she has always respected Addison's professional skills and where they are. It's one of my favorite scenes -- you see in the promos, the 'Get me Meredith Grey,'" she teased, sharing that she sticks around for at least two episodes. "So we get to work together in this episode and there's some good personal stuff that comes up too. It will be really surprising and satisfying to fans but in a very surprising way. That's all I can say."

With the renewed interest in her character amid her return, could Walsh foresee a future where she pops back into Grey's for an extended period of time? She didn't exactly close the door on the idea, but noted there were logistical obstacles that would make a longer arc difficult.

"I don't know about that," she admitted. I've got other commitments right now and I am kind of halfway around the world most of the time," Walsh said, referring to her home base in Australia. "She's the classic unavailable mother character. Like, bye, I’m here and then I’m gone. I did two episodes and then you’ll see what happens."

Grey's Anatomy airs Thursdays at 9 p.m. ET/PT on ABC. For more, watch below.

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