It is not only the patients' stories that make Grey's Anatomy so intense, but also those of the staff who work there. Fittingly for a hospital, a natural fluctuation exists when it comes to the cast and many characters have left the show, only to be replaced by new ones.

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There are however three actors, who have been on the show since the very beginning and are still going strong today. Find out who they are below!

Ellen Pompeo is the undisputed star of the show

Ellen Pompeo has played "Dr. Meredith Grey" from day one, who starts out as a surgical intern in season one and works her way up the ladder to become head of general surgery. Justin Chambers, best known as "Dr. Alex Karev" was part of the cast from the start as well, until he made his exit just last month

READ MORE: Ellen Pompeo shares rare video of her daughter while social distancing

Chandra Wilson and James Pickens Junior are also members of the core cast. Wilson plays tough but lovable "Dr. Miranda Bailey" and Pickens Junior stars as "Dr. Richard Webber".

Fans were devastated when "McDreamy" left

Just as those three have been on board for numerous years, many popular characters have left the hospital as well. When Patrick Dempsey, who played handsome heartthrob "Dr. Shepherd" left, it was a tough blow for many fans. They were just as shocked though, when Sandra Oh's character "Dr. Cristina Yang" left Seattle at the end of the tenth season to take on the position of manager at a private clinic in Switzerland.

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Katherine Heigl and T.R. Knight, two fan favorites from season one, also left the show early on. Heigl's character "Dr. Izzy Stevens" died from cancer in season six, while Knight's character, "Dr. George O’Malley" died in a tragic bus accident at the end of season five.

Ellen Pompeo

Shonda Rhimes knew exactly who should play "Meredith Grey"!

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