One of the longest-running television programs in history, Grey's Anatomy will debut its 19th season in October 2022. After the season 18 finale, fans of the show cannot wait to see their favorite doctors again and watch as their personal and professional lives are once again flipped upside down.

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Grey's Anatomy is famous for creating epic love tales with Meredith Grey (Ellen Popeo) and Derek Shephard (Patrick Demsey), Mark Sloan (Eric Dane) and Lexie Grey (Chyler Leigh), as well as its iconic friendships between Cristina Yang (Sandra Oh) and Meredith, Derek and Mark, and so on. However, due to the show's large cast of characters, not all relationships can be observed, and some excellent ones are missed. Thus, here they are.

Miranda Bailey and Derek Shepherd

Two people are laughing hard together

Despite having a rocky beginning, the two grew closer than their fans realized. Bailey (Chandra Wilson) and Shepherd don't share much in common other than that they both hold the position of Chief of Surgery, albeit not simultaneously, and they both have an unwavering affection for Meredith Grey and the hospital.

The two hardly ever spend any obvious sweet moments together, yet they are always there for one another. For instance, Bailey observed Derek becoming emotional following a particularly dramatic case in "Into You Like a Train" (season 2, episode 6) and halted the elevator to give him some space, or when he repays the favor following George's passing in season 6. Friendship does come in various shapes and sizes.

Meredith Grey and Jackson Avery

Two surgeons make annoying faces

Despite Jackson Avery's (Jesse Williams) tempestuous relationship with Meredith during his rocky season 6 premiere, both eventually and gradually mellowed. As the show continues, fans can witness how the two bonded on a shared understanding of what it's like to pursue a career in surgery while living under the pressure of carrying on a powerful and famous last name.

In addition to the fact that both of their powerful surgical mothers were and are involved with Richard Webber (James Pickens Jr.), they also shared a tremendous ambition to be better than what destiny plans for them and to work harder than anybody else in the room. The two were also the final members of their residency class before Jackson’s departure in "Tradition" (season 17, episode 15), which demonstrates how strong their bond is.

Cristina Yang and April Kepner

One is saying something with an annoyed face while the other is shocked

One is regarded as Grey's Anatomy's snarky queen and unstoppable force, and the other is the virgin from Ohio, who initially seemed to be the pain in everyone's bottom. Although Cristina Yang and April Kepner (five) initially don't seem to fit in each other’s picture, they soon form an iconic duo who, while rolling their eyes and making sarcastic remarks, would always have each other's back.

For instance, Cristina loved and praised the fact that April dared to leave Matthew (Justin Bruening) at the altar for Jackson in "Get Up, Stand Up" (season 10, episode 12) or every time April was privately impressed by Cristina’s abilities, she made a face.

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Richard Webber and Callie Torres

A patient and his wife are talking to a doctor

There were many memorable moments that highlighted Richard Webber and Callie Torres’ (Sara Ramirez) friendship, such as the night he unintentionally discovered her dancing in her underwear in the hospital's makeshift studio (“I Am a Tree,” season 3, episode 2) or the time they pretended to be a couple to visit a rival hospital (“The Face of Change,” season 9, episode 14).

Despite spending less time on screen together than in other pairs, the two consistently steal the show with their humor or unwavering loyalty to one another and to the hospital.

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Callie Torres and Addison Montgomery

Two women are talking and laughing during lunch

Though Addison (Kate Walsh) left Seattle before their friendship could develop into another iteration of "twisted sister," it nevertheless won over fans thanks to their fantastic chemistry and the connection Mark Sloane established between them.

Like Cristina and Meredith, Addison and Callie are constantly there for one another without using large expressing words or their trademark catchphrases. Examples include when Callie gave birth to Sofia (Eva Ariel Binder) after an accident (“Song Beneath the Song,” season 7, episode 18) or Callie is comforting Addison in the restroom after an upsetting case (“Where the Boys Are,” season 3, episode 7).

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Cristina Yang and Callie Torres

Two women are talking and laughing at a party

Fans could forget the fact that Callie agreed to let unstable Cristina cut her hair (“Something's Gotta Give,” season 7, episode 8) and that they used to live together before Arizona Robbins (Jessica Capshaw) moved in during season 7 of the show, proving that their friendship is one of the most underrated in the show.

Cristina did cry over cereal with Callie, demonstrating that she trusts her more than she lets on despite not being attached to anybody but Meredith. Additionally, the two can be destructive because of their intolerable demeanor, sarcasm, and the length they would go to protect their loved ones.

Richard Webber and Alex Karev

A man is standing behind the kitchen island and talking to one sitting on the opposite

Richard was one of the few people who could keep the haughty surgical intern Alex in check when he arrived at the hospital. Richard is also one of the few individuals Alex admires and regards as his closest friend and mentor.

Even though they don’t share many tender and emotional moments like other bromances on the show, Richard and Alex always silently support each other in every situation. For instance, when Richard advised Alex to apply to be the Chief of Surgery at Pacific-North Hospital so he could recruit Richard (“Nothing Left to Cling To,” season 16, episode 1).

Cristina Yang and Dr. Thomas

An old man and a woman talking on the bench

Yang and Dr. Thomas' (William Daniels) friendship must rank as one of Grey's Anatomy's most underestimated friendships. The two may have a rocky beginning, like most of the series' most enduring and underappreciated friendships, but they still manage to develop into Cristina's most heartbreaking and profound connection.

He brought her a danish, provided her professional and personal advice, and eventually, his passing drove her back to Seattle. Their friendship may be short-lived, but to Cristina, Dr. Thomas is more than a friend; he was her mentor and the father figure she lost. Despite being the show's shortest friendship, it certainly stays the longest in viewers' hearts.

April Kepner and Owen Hunt

Two doctors are listening closely to other fellow doctors

Owen Hunt (Kevin McKidd) is always April Kepner's biggest supporter and believes in her potential, even though she was twice let go from Seattle Grace; everyone initially finds her extremely annoying and unbearable.

April must be one of the few individuals Owen trusts with his life, besides his loved ones and romantic interests. Examples consist of in addition to asking April to be his best man ("Family Affairs," season 12, episode 24) and going all the way to her hometown to recruit her again ("Love the One You're With," season 9, episode 3), Owen also trusts April enough to run his ER in his absence.

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