Grey's Anatomy is one of the most popular and longest-running shows of all time. The medical drama follows the life of Meredith Grey and her journey at Grey Sloan Memorial Hospital. The show is an emotional rollercoaster like none other, featuring romance, friendships, death, and despair.

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Grey's Anatomy fans stuck around through it all, especially the numerous deaths that occurred in the series. From heart failures to brain aneurysms to tragic accidents, the show has seen some unexpected and heartbreaking deaths.

Updated on September 19, 2022 by Samantha McPhee: Grey's Anatomy has been renewed for a 19th season and fans can be sure that Grey Sloan Memorial Hospital will be home to plenty of tragic storylines. Until then, fans can look back at the most upsetting deaths in the critically acclaimed medical drama.

10 Derek Shepherd

Season 11, Episode 21

Patrick Dempsey as David Shepherd in Grey's Anatomy

Derek Shepherd's demise is the saddest death in Grey's Anatomy. When he witnessed a car crash on his way to the airport, being the hero that he is, he saved four people. After getting back into his car, he received a phone call and missed seeing an oncoming semi that ended up hitting his car.

Derek's tragic accident, and the consequent brain damage that led to his death, left Meredith Grey and every fan heartbroken. As such an important character, to think that Derek's death could have been avoided is nerve-wracking.

9 George O'Malley

Season 6, Episode 1

George O Mally in Grey's Anatomy

George O'Malley's death was quite out of the blue. He got hit by a bus when he jumped in front of it to try to save a woman's life. The accident left him unrecognizable. However, Meredith went in to check on her John Doe patient and he traced "007," his nickname, on her palm. Meredith's realization that the unknown patient was George left her aghast.

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George's brain swelled up during surgery, leading him to be pronounced brain-dead. Eventually, he was sadly taken off life support. George was a very compassionate, kind, and dedicated person. He sometimes doubted himself but ultimately was very good at his job.

8 Denny Duquette

Season 2, Episode 27

Denny Duquette from Grey's Anatomy

Jeffrey Dean Morgan excellently portrayed Denny Duquette, whose story is nothing short of a tragedy. He arrived at Grey Sloan Memorial when he was already on his way to death's door. Despite the circumstances, he and Izzie fell in love. Their love drove Izzie to take extreme actions so that Denny could receive a heart transplant and their tragic love could have a happy ending.

Unfortunately, Denny and Izzie just weren't meant to be. Although his surgery was a success, he died of a stroke, which was a complication of the surgery. This was one of the most gut-wrenching deaths in the show and one that fans wish never occurred.

7 Lexie Grey

Season 8, Episode 24

Lexi Grey from Grey's Anatomy

Meredith's sister, Lexie Grey, was involved in a plane crash with Cristina, Meredith, Mark, Arizona, and Derek while they were on their way to another hospital for surgery. The tail section of the plane broke off, resulting in a crash into the woods. Lexie was trapped under a piece of the plane that crushed her pelvis and legs.

Lexie succumbed to her injuries while holding Mark's hand. The last conversation she had was with Mark where he told her he truly loved her. Lexi's death was tragic and unexpected, and unfortunately, there was nothing that could have saved her.

6 Mark Sloan

Season 9, Episode 2

Mark Sloan lying in a hospital bed in Grey's Anatomy

Mark sustained injuries in the plane crash that resulted in Lexie's death. His injuries were thought to be minor at first, but after further examination, they found out that he had cardiac tamponade. Sadly, this meant that there was fluid surrounding his heart. However, they managed to drain the fluid and get him to the hospital.

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In the hospital, Mark spent two months with his state declining until he briefly awoke before falling into a coma. As stated in his will, he was taken off life support after 30 days. It was a tragic fate for such a beloved character.

5 Andrew DeLuca

Season 17, Episode 7

Andrew DeLuca from Grey's Anatomy

Andrew DeLuca was a doctor who was committed to making a difference. He identified a case of human trafficking but, unfortunately, people were a little late in believing his claims.

Although they were eventually able to help, Andrew was stabbed while chasing the criminal. He suffered a cardiac tamponade that resulted in his heart giving up. He spent his final moments in a dream-like state with Meredith and his deceased mother. In the end, he walked away with his mother while others mourned his death. It was a sad sequence, especially when DeLuca said that "he wanted to do more."

4 Doc

Season 2, Episode 27

Doc from Grey's Anatomy

Although Doc was a dog, his death made everyone cry. Even though he caused chaos, he was a good dog who was always there to give comfort. When he fell sick, Derek took him to the vet and found out that Doc had bone cancer.

The vet told them their options but the best-case scenario was that Doc had a year to live. His state was already pretty bad, so they made the tough decision to put him down instead. Meredith and Derek stayed with Doc while he passed away. They buried him at the clearing near Derek's trailer, which overlooked the water.

3 Susan Grey

Season 3, Episode 23

Susan Grey from Grey's Anatomy

Susan Grey was Meredith Grey's stepmother. She came to the clinic with complaints of hiccups and acid reflux, which the staff treated her, but Susan quickly returned with more severe symptoms of fever and cramps. She turned out to be septic and had toxic megacolon. Even after the doctor's best efforts, they were unable to save her.

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Susan encouraged Meredith to fix her relationship with her father, Thatcher Grey. She shared a friendly bond with Meredith, especially after the death of Meredith's biological mother, Ellis Grey. However, Susan's shocking demise cut their relationship short.

2 Heather Brooks

Season 10, Episode 2

Heather Brooks in Grey's Anatomy

Heather was an intern at Grey Sloan Memorial Hospital. During the superstorm, she was asked to find Dr. Webber. She found him in the generator room suffering from an electrical shock. When she approached to help him, she accidentally stepped into a puddle that was charged with electricity. This caused her to fall and hit her head on a generator box.

The hospital staff rushed Heather into surgery and repaired her subdural brain bleed, but she succumbed due to her brain swelling too much. She was an overly enthusiastic intern, even if most people found her annoying. However, everyone was saddened by Heather's death, especially since she died trying to help someone.

1 Adele Webber

Season 9, Episode 10

Adele Webber and Richard from Grey's Anatomy

Adele Webber had a devastating story in Grey's Anatomy. She suffered from Alzheimer's, which led to a series of events that included forgetting her own husband. She ended up having a brain aneurysm and while the doctors were able to treat it successfully, the surgery was too much for her heart to handle. Tragically, she passed away due to a heart attack.

The scene that got through to the audience the most was when her husband, Richard Webber, sang "My Funny Valentine" to calm her down. The song made her relive her wedding and brought tears to everyone's eyes.

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