'Grey's Anatomy': 20 defining moments of Its first 10 years

Ellis has Alzheimer's (Season 1, Episode 1)

The best thing intern Meredith Grey had going for her was her name: After all, being the daughter of the esteemed Ellis Grey looks great on paper. And that’s what made the realization that Ellis was suffering from Alzheimer’s all the more upsetting. Not only was Ellis no longer a great surgeon, but as we’d later find out, she wasn’t a great mother either. —Samantha Highfill

The first "McDreamy" (Season 1, Episode 2)

Grey’s Anatomy wouldn't be Grey’s Anatomy without its "Mc" nicknames. In season 1, Cristina was the first one to label Derek Shepherd "McDreamy." From there, we got McSteamy, McHottie, McVet, McVomit, and so much more. Plus, this episode also contained another Grey's landmark: the first elevator kiss. —Samantha Highfill

Addison arrives (Season 1, Episode 9)

Meredith and Derek’s relationship was filled with drama from the start, but things got even more complicated when his wife, Addison Shepherd, greeted the new couple at the hospital. Meredith didn’t know Derek was married until that very awkward moment, and Derek didn’t know Addison was coming to visit, so it was an unfortunate surprise all around. Although Addison first comes off as an evil, Cruella de Vil-type character, she went on to become one of the show’s strongest players—and even earned herself a spinoff in the process. —Ariana Bacle

"You're my person" (Season 2, Episode 1)

Cristina tells Meredith she put her name down as her emergency contact by saying, "You’re my person." From that moment on, the relationship between these dark-and-twisty individuals is unbreakable—even when they go on to have an episodes-long argument in a later season—and becomes a model for positive depictions of female friendships in pop culture. —Ariana Bacle

"Pick me, choose me, love me" (Season 2, Episode 5)

When Addison first showed up in Seattle, Meredith tried to fight her feelings for Derek—considering he was, you know, a married man. But as the season started to unfold, Meredith realized that her love for Derek couldn’t be ignored, and everything came to a head in one of the show’s most memorable moments. Not only did it demonstrate Shonda Rhimes' ability to write one hell of a romantic speech, but within the show's universe, it also let Derek know that Meredith was still an option. —Samantha Highfill

The bomb (Season 2, Episode 16/17)

This two-parter demonstrated just how great this show could be, and also set many things in motion: George helped Bailey give birth to her son, Alex and Izzie slept together, Cristina realized the extent of her feelings for Burke, and Derek was forced to imagine a life without Meredith. (And he didn't like it.) —Samantha Highfill

Izzie cuts the LVAD wire (Season 2, Episode 25)

Izzie tried to save Denny’s life by cutting his LVAD wire, which stopped his heart—and hypothetically put him higher on the list for an immediate heart transplant. Her plan worked, but he ended up dying anyway from a stroke—and she ended up unraveling, quitting her job at the hospital (but eventually returning to open up a free clinic using the millions of dollars Denny left to her). —Ariana Bacle

The ferry crash and Mer's drowning (Season 3, Episode 16/17)

First and foremost, the ferry crash was symbolic of Meredith’s state of mind—just seasons earlier, Derek had talked about his love of Mer as his love of "ferry boats." Add to that the fact that Meredith’s drowning set off a number of changes: From McSteamy and McDreamy finally acting like friends to Derek questioning whether Mer drowned on purpose, multiple relationships would never be the same. And for Meredith, her time in limbo allowed her to say goodbye to her mother, who finally told her daughter that she was "anything but ordinary." With that, Meredith woke up. Ellis didn't. —Samantha Highfill

Burke leaves (Season 3, Episode 25)

Burke and Cristina were so closed to getting married—so close!—but Burke backed out at the very last minute after realizing he didn’t want to marry Cristina as she was: He wanted Cristina to be a different woman completely, and it was best for both of them for him to let her go. With that, Burke was gone from the show (until a brief appearance in season 10), and Cristina was left heartbroken. —Ariana Bacle

Meredith and the house of candles (Season 4, Episode 17)

Derek loved Meredith even when she was dark and twisty, but their relationship was never going to work until she dealt with some of the things in her past. It wasn’t until Meredith went to therapy that she was finally able to go to Derek, create a house of candles, and tell him that she was “whole and healed” and ready to be together forever. They haven’t broken up since. —Samantha Highfill

Izzie realizes that she’s sick (Season 5, Episode 13)

Spoiler: When your dead fiancé shows up and the two of you engage in some ghost sex, it's probably because something’s not right in your head. And for Izzie, it all stemmed from a brain tumor. The moment she figured that out, her life changed... as did the show. —Samantha Highfill

Owen chokes Cristina in his sleep (Season 5, Episode 19)

Serving as a trauma surgeon for the U.S. Army can mess anyone up, Owen included. The extent of his PTSD was revealed when he strangled Cristina in his sleep one night, resulting in their (temporary) break-up and showing that even those with the toughest of exteriors—Owen is the same guy who stabbed a bunch of pigs just so his employees could operate on them—might be hiding unimaginable struggles. —Ariana Bacle

Meredith and Derek’s Post-it wedding (Season 5, Episode 24)

With Izzie’s illness, George’s decision to join the army, and a very injured John Doe in the hospital, Meredith and Derek’s wedding was seeming more and more unlikely. So when a frustrated Meredith couldn’t find the time, Derek came up with a solution: They’d write their vows on a Post-it note, sign it, and then he’d kiss the bride. The couple then promised to love each other (even when they hate each other), and to never run—among other things. Eventually, they’d have to head to City Hall so that they could adopt Zola, but as far as they’re concerned, that Post-it note represents their marriage... and that’s why it still hangs above their bed. —Samantha Highfill

George dies (Season 5, Episode 24)

An unrecognizable patient is admitted to the hospital after getting hit by a bus. It turns out to be George, who reveals his identity by using his fingers to write "007"—the nickname Karev gave him way back when—in Meredith’s palm. This revelation is all the more shocking because Izzie, deep into her cancer struggle, is also on the brink of death. She ends up making it; George does not. Out of all the many, many Grey’s deaths, George’s continues to hit the hardest—both because of how shocking it was and because up until then, George was really the heart of the show. —Ariana Bacle

Hospital shooting (Season 6, Episode 23/24)

After introducing a number of new characters via a hospital merger, Grey's seemed to recognize its mistake: In the season 6 finale, a number of those new faces were killed by a gunman. Along with getting rid of the less-loved characters, the shooting also nearly took down Derek (and made standing in an operating room an impossibility for Cristina). —Samantha Highfill

Callie tells Arizona she’s pregnant (Season 7, Episode 12)

While Arizona was off in Malawi, Callie had sex with Mark—and got pregnant with his baby. Then Arizona came back to the U.S. early for Callie, and was welcomed with the news that, surprise, her ex-girlfriend was pregnant with someone else’s child. This baby would go on to bond Callie and Mark together forever, even after his death in season 9, and create both obstacles and plenty of joy for first-time moms Callie and Arizona. —Ariana Bacle

Cristina unwittingly operates on Henry (Season 8, Episode 9)

Knowing that robot Cristina was the best heart surgeon in the hospital, Teddy asked Owen and company to trick Cristina into operating on her husband. But even the robot couldn’t save Henry. It was a loss that would change Teddy forever, and an operation that would change Cristina—once she found out the identity of her patient. —Samantha Highfill

The plane crash (Season 8, Episode 24)

As if life weren't already hard enough for the people of Seattle Grace Mercy West, a few of them got in a plane crash that left Lexie and Mark dead, and Arizona so injured that Callie eventually had to make the call to amputate her leg. The deaths, the amputation, and the crash itself caused serious consequences that left the survivors—Derek, Cristina, Meredith, and Arizona—reeling in their own, occasionally destructive, ways. And the aftermath didn't just last for a season: Callie’s decision to amputate Arizona’s leg came up again in the show's current season, and is one of the main reasons why their relationship is (for the moment) over. —Ariana Bacle

Adele dies (Season 9, Episode 10)

In a way, Webber had lost Adele already, after she started to show signs of Alzheimer’s and eventually found a new boyfriend in her assisted living facility. But that didn’t make her death any easier for him: She met her end right before Bailey’s wedding, where Webber told Meredith (but not Bailey) the truth about Adele’s passing. Then, as Bailey and Ben swayed through their first dance, he daydreamed he and Adele were in their place. Even though Adele was just a supporting character, she played a huge role in the show from the beginning. Her death signified an era—in both the show’s and Webber’s life—coming to a close. —Ariana Bacle

Cristina leaves Seattle for good (Season 10, Episode 24)

Cristina leaving for Zurich wasn’t just important for her character’s development, but for Meredith’s: She leaves Grey by saying, "[Derek’s] very dreamy, but he’s not the sun. You are." Those words have stayed with Meredith throughout the current season, and she’s made an obvious effort to focus on herself and her own success over her husband’s. (It helps that she and Derek are going through a bit of a rough patch, but still.) —Ariana Bacle