Kate Walsh confirms she's returning to 'Grey's Anatomy' as Dr. Addison Montgomery

"Well, well, well, would you look who it is?" Walsh said in the video posted to the official Grey's Twitter feed. "That's right, my loves. Dr. Addison Montgomery is coming back to Grey Sloan Memorial Hospital, and I'm so excited to be home again! Joining [show creator] Shonda [Rhimes], Ellen [Pompeo], and the rest of the incredible cast."

"This season — 18, whew — just wait until you see what she has in store for you," the 53-year-old actress continued. "The new season premieres Sept. 30 on ABC, so stayed tuned."

Walsh first appeared on the historic medical drama in the first season finale, coming to Seattle to surprise her estranged husband, Dr. Derek Shepherd (Patrick Dempsey), who had since moved on with Dr. Meredith Grey (Pompeo). 

The coveted neonatal surgeon became a series regular through the second and third seasons. Walsh ultimately left to lead Private Practice (2007-13), but she returned occasionally to Grey's in guest appearances up until the Season 8 flashback episode "If/Then" that aired in February 2012.

Outside of the Grey's universe, Walsh has starred in other hit series such as 13 Reasons Why, The Umbrella Academy and Emily in Paris.

It was previously reported last month that Grey's next season will include Kate Burton reprising her role of Dr. Ellis Grey, renowned surgeon and mother to Meredith who died in Season 3.