Derek Shepherd is one of the most popular characters on Grey's Anatomy and for good reason. His journey is a fascinating one, as he falls in love with Meredith when she's an intern, realizes that his marriage to Addison is over, and struggles to balance family and work. His absence is definitely felt on the beloved hospital drama and his season 11 death will never be forgotten.

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While Derek's time on Grey's Anatomy involves many dramatic storylines from his relationship with Meredith to his brilliance as a surgeon, there are several episodes that stick out as the most memorable and important.

"A Hard Day's Night" (S1, E1)

Derek and Meredith smiling on Grey's Anatomy

It's interesting to compare the Grey's Anatomy pilot to the series, and in the first episode, fans see the beginning of the Derek and Meredith romance. While the characters meet in a bar and it seems like they'll just have a one-night stand, they see each other at the hospital and realize that they can't stay away from each other.

Derek's realization that Meredith is an intern is fun and juicy to look back on, as this creates a lot of drama right away. While not as intense as some others, this is one of Derek's greatest episodes as it's the moment when his life changes forever as he will never be able to let Meredith go.

"If Tomorrow Never Comes" (S1, E6)

Derek leaning against a wall on Grey's Anatomy

Once Derek and Meredith realize that they work in the same place, they vow to keep their relationship a secret. Unfortunately for them, Bailey sees them in this episode and doesn't want Derek to allow Meredith to have opportunities that the other interns won't get.

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This season 1 episode is important since Derek knows that he has to figure out his feelings for Meredith so they don't affect his job, which matters so much to him. Other episodes might move the Meredith/Derek love story in a new direction or create more personal turmoil for Derek, but this one is still a key part of his journey.

"Adrift And At Peace" (S7, E10)

Cristina and Derek fishing on Grey's Anatomy

There are some great friendships on Grey's Anatomy as the doctors have gotten so close over the years. Fans loved watching Derek take Cristina fishing in this season 7 episode.

Derek can tell that Cristina is struggling after the shooting at the hospital, and he feels that a fishing trip will help her heal. Cristina has much more fun than she expects to as she's successful at catching a fish. If Grey's Anatomy fans were to pick their favorite Derek episodes, they would most likely choose ones involving his love story with Meredith, but this one is still really sweet.

"I Am A Tree" (S3, E2)

Split image of Meredith and Finn and Derek on Grey's Anatomy

In this season 3 episode, Meredith lets Derek and Finn know that she wants to date both of them, which is definitely a shock since it's likely they each thought she would choose them.

This episode is a huge deal for Meredith and Derek as he becomes terrified of losing her. While Derek might be a super confident doctor who is used to doing well in his professional life, this episode makes him see that his personal life might not always be as happy and successful. He will eventually realize that he has to fight for the person whom he loves. This isn't the best Meredith and Derek episode, but it's still a dramatic one.

"Remember The Time" (S9, E2)

Derek Shepherd promotional pic for Grey's Anatomy

This is a tough moment for Derek as, after the tragic plane crash at the end of season 8, he's unsure if can use his hand properly ever again. He begins teaching so he can still work at the hospital and make a difference in the industry that he is so passionate about.

Since Derek is at a crossroads here, wondering if he can continue to do the job that he loves, it's a crucial part of his journey on Grey's Anatomy. It's also nice for fans to see Derek be vulnerable and afraid as he often presents himself as totally cool, calm, and collected.

"Good As Hell" (S17, E13)

Meredith confesses that she misses Derek in Grey's Anatomy

Meredith has beach visions in season 17, and in this special episode, Meredith and Derek connect over the traditional wedding that they never had. Meredith tells Derek that their daughter Ellis hates seeing the post-it note from their wedding, as she wanted them to have a real, actual wedding. In an incredibly beautiful and heartbreaking episode, Meredith sees a vision of her and Derek getting married on the beach.

This is one of Derek's most significant episodes as he gets the chance to have some closure with his one true love. Fans were also thrilled at the opportunity to see this couple again, and while it's so sad to watch them in wedding outfits, it feels right.

"Now Or Never" (S5, E24)

Derek and Meredith's post-it note wedding on Grey's Anatomy

Derek and Meredith's post-it note wedding explains their whole romance, as it's offbeat and tells everyone that they don't love tradition.

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Since this season 5 episode features this big moment for Meredith and Derek, it's always going to be a fan favorite episode. This storyline sets the tone for the rest of Derek's time on the show, as he fully commits to Meredith and they are able to plan for the future. Of course, the fact that Derek will die tragically and their romance will be cut short will always hang in the background when fans re-watch this episode.

"Fear (Of The Unknown)" (S10, E24)

Derek Shepard and Meredith Grey from Grey's Anatomy

Derek is thrilled to be offered a job working for the President, but in this significant episode, Meredith tells him that she won't move to Washington, D.C. with him. She loves him so much but can't ignore what she wants out of life, which is to keep working and living in Seattle.

While fans love the romantic scenes between this couple, this season 10 episode just might be the most meaningful for these characters. It's a true crisis as Derek and Meredith can't agree on how to move forward with their relationship. While they want to be together, their careers are taking them to different places.

"Who's Zoomin' Who?" (S1, E9)

Derek and Meredith talk to Addison on Grey's Anatomy

Of every Grey's Anatomy season finale, this is one of the most intense, since Meredith learns that Derek is married to Addison.

This is a shocking moment in this favorite relationship, and it's strange and confusing that Derek wouldn't tell Meredith that he has a wife. Since Derek behaves so poorly here, it can't be ignored, and this moment also sets up a dramatic and compelling season 2 of the show. Fans are riveted, wondering if this couple will sort things out and what will happen to Addison, who is a strong and fascinating character in her own right.

"How To Save A Life" (S11, E21)

Meredith lying with Derek in the hospital on Grey's Anatomy

The episode when Derek dies is definitely his most dramatic and it's the one that viewers will never stop thinking about. It's particularly awful since it seems like his death doesn't have to happen at all, since Penny has trouble saving his life and Derek ultimately leaves Meredith and their children behind.

When fans look back on Derek's days on Grey's Anatomy, they can't help but think about the harsh and heartbreaking way that his story ends. Since this episode leads to so many massive changes for all the characters who love Derek, it's his number one episode.

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