Kate Walsh – Addison Montgomery Then
Addison shocked viewers in the season one finale when it was revealed she and Derek were still married, creating tension with his new girlfriend, Meredith. After the love triangle was resolved and Addison and Derek divorced, producer Shonda Rhimes created the spinoff Private Practice with Kate Walsh as the lead. The show featured successful crossovers with Grey's Anatomy but ended after five seasons in 2013.
Kate Walsh wasn't done with Seattle Grace, though. She returned to Grey's Anatomy in its 18th season as Dr. Addison Montgomery. Her appearance was highly anticipated by fans, who were thrilled to see her character back on the show after such a long absence.
