Some TV series do not survive the pilot, certain ones only last for one season, and others extend over time, managing to captivate the audience over and over again. Grey's Anatomy is one of the longest-running television shows in history due to its success with audiences. Since the pilot, a lot has happened in this hospital.

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Changes in the series have been made after the pilot or been presented over time during the seasons. After fifteen years and sixteen seasons, Grey's Anatomy retains many aspects of its essence, but it has also seen many transformations in its history, which have allowed viewers to remain hooked on the plot.

Same: The Relationship Between Cristina and Meredith

Meredith and Cristina dance while holding alcoholic drinks in Grey's Anatomy.

One of the best relationships in the whole series is the one between Cristina and Meredith. After Sandra Oh leaves the show, Meredith continues to talk to her occasionally on the phone. Since the pilot, the two women bonded and there was no rivalry whatsoever, even though, at times, there was tension and fights between them.

The great depth of their friendship has allowed the relationship to survive many things without problem, such as distance. They never apologize for who they are, they created an instant bond, they have the right closeness for the kind of person they are and they love to dance to de-stress and just be happy. When Cristina left, Meredith had to find another friend to be her "person" and she chose Alex to take the place, but as Alex Karev himself said, Meredith doesn't need anyone, she is her own person, but they will always continue to be friends.

Changed: Meredith's Confidence

Meredith Grey smiling

Most interns at Grey's Anatomy begin with excitement and fear, Meredith was no different. Being the daughter of a famous surgeon didn't give her confidence from the start, it probably played against her. As she says in the pilot, her mother tried to dissuade her from studying medicine, because for Ellis Grey, Meredith didn't have what it took to be a surgeon.

Meredith is lost in the pilot, she highlights it from the first voice-over to the end. She doesn't have a good reason to be a doctor, but she has plenty of reason not to quit, so she continues. Her perseverance helped her to know that she had what it takes to succeed as a great doctor. The confidence she gained after every case, until she became one of the most respected surgeons in the country.

Same: The Voice Over

Meredith and Derek in an elevator in Grey's Anatomy

Grey's Anatomy is characterized by the voice-overs at the beginning of the show and at the end, this aspect has been maintained since the pilot "A Hard Day's Night." This detail makes the episodes closer to the viewer, in order to make them more empathetic with Meredith and her friends.

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The narration is always present, but it wasn't originally thought of that way. The choice was made by Shonda Rhimes when she noticed something was missing. It was a good decision that gave meaning to much that happened on the screen, through thoughtful monologues.

Changed: Alex Karev

Alex Karev is one of the most beloved characters in the series, as well as one of the most visible on screen (16 seasons), but this role was a last-minute decision. After filming the pilot, the producers wanted to have an additional male character to serve as an antagonist, so Justin Chambers was added in post-production for some scenes.

In the second episode Alex starts to be more important for the story and also becomes part of Miranda Bailey's team of interns, after he is reassigned from Jeremy's group. These changes had to be made after the pilot to make sense of his entry into the group of the five friends. In addition, the character evolves from being the abusive one to one of the closest to his friends and patients.

Same: The House

Meredith's house has appeared since the pilot, and almost every Grey's Anatomy doctor has passed through it, not only during meetings but also living there. Although in the first scene of the pilot Meredith tells Derek that she will sell the house, she finally explains to her mother that she decided to stay and rent the additional rooms.

The first ones to live in it were Izzie and George, but also at some point in the story it was inhabited by Callie, Alex, Derek, Jo, Lexie, Cristina, April, Jackson, Arizona, among others. When Derek and Meredith moved into their dream house, she sold it to Alex, but when Derek died Meredith bought it back. Since then, she has lived there with her children and her sisters Maggie and Amelia. So, the house has always been an important part of the story and has brought them all together.

Changed: The Nazi

George, Baiely, Meredith, Alex, and Cristina standing in the hospital together on Grey's Anatomy

Miranda Bailey was known at first as the Nazi, for her strong character and the way she treated the interns, which was terrifying for the new ones. She wasn't around to play games and had a clear goal to pursue no matter what.

Although Miranda retained that determination to fulfill all her ambitions, she grew with her character. Dr. Bailey became a guide for her students and a friend to those who survived the early stages of their work as doctors.

Same: The Deaths

Alex holding sick Izzie

They couldn't do a series on medicine without death. Not all patients could be saved, even though these people are among the best doctors in the country. From the pilot, they wanted to show the fragility of human life.

But at Grey's Anatomy, death is not only a matter of patients, it is also very present within the medical staff, where tragic accidents and illnesses have made part of the cast change constantly. George O'Malley makes a kind of prediction during the pilot, he asks Meredith if they will survive, and although he refers to the period as interns, the phrase is key to predicting his future and that of many others.

 Changed: The Interns

Cristina lies in a hospital bed as her intern friends hover around in Grey's Anatomy.

During the pilot it is mentioned that there are twenty interns starting on the same day as Meredith and six of them are women. During this first episode it is seen how they are organized in groups of four and five, while they wait in the changing room, they are also present in the gallery during O'Malley's first operation and at lunch time.

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Although there are a lot of interns (extras) in the pilot, they did not continue their appearances. The exclusion of the rest of the interns makes the spectators forget about the fact that more actors played this role and concentrate only on Cristina, Meredith, Izzie, George and Alex.

Same: The Technical Aspects

For Grey's Anatomy it is important to show the maximum veracity during the high number of medical scenes that are done in the show, for this, they have medical advisors that guarantee that the terms used are the correct ones and that the procedures are being done in the right way.

These aspects have not become more flexible over time, because although the writers and actors know more about medicine (after 15 years) than any other media worker, they are not doctors.

Changed: The Characters

Many television series don't maintain all the actors they had from the beginning and Grey's Anatomy is characterized by renewing the cast quite often, keeping only a few. Also, it is very difficult for the same actors to continue for 15 years.

Of the original cast, only Meredith, Richard Webber and Bailey are still in the picture. The first of the five interns to say goodbye to their role was George, who died after a bus accident. And the last was Alex in season 16, who had a bittersweet exit for fans who wanted to continue watching him on screen.

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