16. Heather Brooks Heather was a surgical intern during seasons 9 and 10. Following a superstorm, she found Dr. Webber suffering from an electrical shock in the generator room. While trying to help him, she stepped in an electrified puddle herself, causing her to slip and hit her head. She died from brain swelling. Ron Tom
15. Dr. Craig Thomas Dr. Thomas worked at the Mayo Clinic, and mentored Cristina during her boards. Due to his old age, he suffered a heart attack while in the operating room. ABC
14. Henry Burton Henry was a former pro baseball player who worked as a shipping clerk, and when he came to the hospital with Von-Hippel-Lindau syndrome without insurance, surgical resident Teddy Altman proposed that they get married so he could be on her insurance. After several surgeries and a diabetes diagnoses, a CT scan revealed a tumor near his heart. Cristina and Dr. Webber immediately operated on his heart, but he died during surgery because the tumor eroded his pulmonary artery. Adam Taylor
13. Charles Percy Charles was a surgical resident at Sloan Memorial who was tragically murdered when the husband of a deceased patient became an active shooter looking to murder the surgeons who operated on his wife. When the shooter asked Charles if he was a surgeon and Charles said yes, he got shot. His death was particularly tragic because on his deathbed, he told Bailey to tell Reed (who also died during the shooting) that he loved her. Eric McCandless
12. Reed Adamson Reed was also murdered by widower-slash-shooter Gary Clark, who asked her to help him find Derek Shepherd, which she refused. He shot her in the head, and her best friend and roommate April Kepner slipped in a puddle of her blood. Ron Tom
11. Susan Grey Susan Grey was Meredith's stepmother, and the mother of Lexie and Molly Grey. She first arrived at the hospital complaining of hiccups and acid reflux, and after being sent home twice, she returned with a fever and cramping and went into surgery. She died after surgery after suffering sepsis and a toxic megacolon, and Meredith's father blamed Meredith for Susan's death. Vivian Zink
10. Dylan Young Dylan was in charge of the Seattle Police Department Bomb Squad during the bomb scare that panicked Sloan Memorial Hospital during season 2, episode 17. (A World War II fanatic built a bazooka in his backyard and then became impaled with the explosive, which endangered the hospital because there was literally a bomb inside of him.) After Meredith successfully removed the explosive from inside the patient's chest, she handed it to Dylan, and it exploded, killing him. Peter "Hopper" Stone
Doc the Dog Meredith adopted Doc to help her get over Derek after he got back together with Addison (played by Kate Walsh). But when Meredith discovered Doc had bone cancer, she decided to put him to sleep. And well, it's one of the saddest Grey's death scenes...even if it is about a dog. ABC
8. Adele Webber Adele (played by Loretta Devine) suffered from Alzheimer's. While she died offscreen, it was the scene where Richard (James Pickens Jr.) operated on her and sang "My Funny Valentine" (leading her to believe it was their wedding night) that had everyone a complete mess. Kelsey McNeal - Getty Images
7. Ellis Grey Ellis (Kate Burton) wasn't exactly an all-star mother to Meredith, but her death, also from Alzheimers, rocked Meredith's world. Fans did see Meredith get a bit of closure, however, when she nearly drowned and saw her mother. In that episode, Ellis tells Meredith she's anything but ordinary and that she needs to stay alive. It's a mother-daughter moment only Grey's could pull off. Michael Desmond - Getty Images
6. Samuel Norbert Avery When Jackson Avery (played by Jesse Williams) and April (Sarah Drew) had a baby, it seemed like a moment to rejoice. But viewers quickly the infant had a life-threatening diseaseand he died shortly after birth. Eric McCandless - Getty Images
5. Mark Sloan McSteamy (played by Eric Dane) died after Lexie as a result of injuries he sustained in a plane crash they were both in. Because Mark's will stated he wanted to remain on life support for 30 days before being taken off of it, fans had to wait through the summer hiatus to learn his fate. Jean Baptiste Lacroix - Getty Images
4. Denny Duquette This one nearly broke us. The prospects for Denny (Jeffrey Dean Morgan) were always grim, given that viewers first met him because he was admitted to the hospital for heart failure. But Izzie Stevens (Katherine Heigl) fell for him anyway, and when he died in her arms, fans mourned right alongside her. Denny did, however, return in ghost formtwice. Once when Meredith nearly drowned, and again when Izzie was was being treated for Stage 4 cancer. Scott Garfield - Getty Images
3. Lexie Grey Not only was Lexie (played by Chyler Leigh) crushed to a death by a a piece of shrapnel from the tragic airplane crash she and Mark were in together, but she took her last breath as Mark admitted his love for her: "Ive always loved you, Ill always be in love with you." I'm not crying, you're crying. Randy Holmes - Getty Images
2. George OMalley The death of George (played by actor T.R. Knight) was one of the worst to witness, perhaps because it was so sudden. After pushing a woman out of the way to avoid an oncoming bus, George ended up getting hit by the bus himself. His injuries were so severe that he was unrecognizablethat is, until he traced "007" (his nickname) on Meredith's hand. He ultimately died, and fans would never be the same. Scott Garfield - Getty Images
1. Derek Shepherd This was the saddest Grey's death of all because I really thought it was the one happily ever after Shonda might let one of her characters have. But when Derek (Patrick Dempsey) suffered brain damage from a tragic accident, we watched Meredith say goodbye to McDreamy. Before she gave the go-ahead to take him off life support, Meredith said, "Derek, it's okayyou go. I'll be fine." Years later, and fans still aren't okay. Are you sobbing yet? Because I sure as hell am. Scott Garfield - Getty Images