Sandra Oh has played Dr. Cristina Yang since the series debuted. She'll exit the series following the end of its 10th season -- but wants to return for the eventual series finale. "Creatively, I really feel like I gave it my all and I feel ready to let her go," an emotional Oh tells THR. "It's such an interesting thing to play a character for so long and to actually get the sense that she wants to be let go as well. [Cristina] wants to be let go and I am ready to let her go. We have to start the process, story-wise, for the Grey's writers to think of why she's going to go."
Tina Majorino recurred on the ninth season of Grey's as Dr. Heather Brooks, one of the new class of interns. The actress, who is a series regular on TNT's Howard Gordon drama Last Ship, will be back in the season 10 premiere and is not expected to return to the ABC medical drama. Meanwhile, the rest of the season nine interns -- Gaius Charles, Camilla Luddington, Jerrika Hinton and Tessa Ferrer -- have all been promoted to series regular for season 10.
Loretta Devine earned an Emmy for her guest turn as Adele, the wife to James Pickens Jr.'s Dr. Richard Webber. After a 22-episode run that began in 2005, the character was heartbreakingly diagnosed with Alzheimer's and died during the ninth season of the drama.
Eric Dane played Dr. Mark "McSteamy" Sloan, Derek's best friend. He initially arrived as a recurring player in season two and was bumped to regular in season three. Following notable relationships with Addison (Kate Walsh) and a fling Callie (Sara Ramirez), the ladies' man never got over Lexie (Chyler Leigh). He ultimately died after injuries sustained in the plane crash that claimed her life and last appeared early in season nine.
Chyler Leigh played Lexie Grey, the younger half-sister to Ellen Pompeo's Meredith Grey. She arrived as one of the new batches of interns in season three and was written out of the series in the season eight finale, the first victim from the deadly plane crash -- but not before finally reuniting with her "person" -- Mark.
Kim Raver's Teddy Altman was brought in during season six as a mentor for Cristina Yang (Sandra Oh). The character was a former Army colleague of Kevin McKidd's Dr. Owen Hunt -- and an ex-girlfriend. Following flings with Mark (Eric Dane), And Dr. Perkins (James Tupper), she fell for a patient named Henry (Scott Foley). She exited the series during the season eight finale when her character -- still coping with Henry's death -- accepted a job at an Army hospital.
Scott Foley first appeared in season seven as Henry, a patient without medical insurance, who befriended Kim Raver's Dr. Altman. The duo, who wed so he could take advantage of her insurance, developed a loving relationship before he died on the table -- during a procedure overseen by Cristina (Sandra Oh), who had no idea she was operating on her mentor's husband. Foley is one of a handful of Grey's alums who have made their way to EP Shonda Rhimes' Scandal, joining Kate Burton and Jeff Perry, among others.
Brooke Smith played Dr. Erica Hahn, the replacement for Isaiah Washington's Dr. Preston Burke. She arrived at Seattle Grace in season four and departed seven episodes into the fifth season. Her coming out speech to Sara Ramirez's Callie Torres continues to be one of the show's most important moments.
Kate Burton has recurred on the series as Ellis Grey -- the mother to Ellen Pompeo's Meredith and a legend at Seattle Grace. The character had a history with Richard Webber (James Pickens Jr.) before developing Alzheimer's. The character died in season three but returned for the alternate-universe episode in 2012.
Kate Walsh played Dr. Addison Montgomery, who first appeared in Grey's Anatomy's season one finale when she arrived as Derek's (Patrick Dempsey) estranged wife. Following three seasons on Grey's, the character was spun off when she moved from Seattle to California, launching Private Practice. The series ran for six seasons before Addison finally earned her happily ever after in January 2013, following a six-season run.
Melissa George played Dr. Sadie Harris, a surgical intern and former friend to Meredith (Ellen Pompeo). She recurred during season five but was not promoted to regular after the series took a different creative direction following the exit of Brooke Smith. The character of Sadie was initially conceived to be a love interest and foil for Erica and Callie (Sara Ramirez).
Katherine Heigl's Izzie Stevens was one of the original interns that launched Grey's Anatomy. The doctor had a penchant for getting too attached to her patients had one of the most memorable -- and later controversial -- story lines on the series after her emotional relationship with Jeffrey Dean Morgan's Denny. The tearful scene after his death still ranks as one of the most memorable moments on the series. Heigl, critical that she wasn't given sufficient material, requested to be released from the series early and, after marrying Alex (Justin Chambers), she was diagnosed with cancer and written out in season six.
Rachael Taylor recurred as Dr. Lucy Fields during season seven. After a relationship with Alex (Justin Chambers), she ultimately took a position in Africa -- a spot he was considering. At the time, it was one of the healthiest relationships Alex has had on the series.
T.R. Knight played George "007" O'Malley, one of the original interns on Grey's Anatomy. The lovable doctor with a heart of gold had relationships with Izzie (Katherine Heigl), Callie (Sara Ramirez) and Meredith (Ellen Pompeo). After requesting an early end to his three-year contract, Knight -- who clashed with co-star Isaiah Washington following the latter's use of an anti-gay slur -- was ultimately killed off after being hit by a bus in a bid to help a pedestrian in a heartbreaking scene that still brings tears to avid Grey's viewers.
Isaiah Washington played Dr. Preston Burke, one of the original doctors on the Shonda Rhimes medical drama. After a string of incidents involving homophobic slurs and clashes with co-stars, ABC opted not to renew Washington's contract and he was dropped from the show in season three.