Kate Walsh returns to ‘Grey’s Anatomy’ as Dr. Addison Montgomery

It's official!

Kate Walsh is set to return to "Grey's Anatomy" and reprise her role as the magnetic Dr. Addison Montgomery.

The actress announced the news on Grey's Anatomy's Instagram page on Friday.

"Well, well, well. Would you look at who it is. 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 Shonda [Rhimes], Ellen [Pompeo], and the rest of the incredible cast, this season 18," she said.

Kate's character, Addison, first appeared in the medical show's season one finale where she introduced herself as the wife of main character Meredith Grey's boyfriend Derek Shepherd.

In 2007, Kate left the show and starred in her own spinoff show called "Private Practice," which saw Addison joining a private clinic in Los Angeles. The spinoff ran from 2007 and ended in 2013.

"Grey's Anatomy," a medical drama series that follows the lives of doctors at a hospital in Seattle, premiered in 2005. Its season 18 is set to premiere on ABC channel on Sept. 30. – Kaela Malig/RC, GMA News