The night ... was March 27, 2005. Television titan Shonda Rhimes knew what she had just created - but audiences still had no idea. The Grey's Anatomy pilot introduced several characters, including the show's protagonist, legacy surgical resident Meredith Grey (Ellen Pompeo). Spunky, undoubtedly intelligent and full of heart, the show wouldn't survive without its titular character - but the ensemble is what keeps viewers tuning in 15 years later. That's why it hits fans hard every time a character gets the boot. Whether they're killed off (as many Grey's characters have been) or simply written out of the show, over a dozen of Seattle Grace's/Seattle Grace Mercy West's/Grey-Sloan Memorial Hospital's finest have left. Keep scrolling to see what T.R. Knight (George O'Malley), Patrick Dempsey (Derek Shepherd) and others have been up to since leaving the ABC hit: