The Entire Timeline Of Grey's Anatomy Explained

"Grey's Anatomy" has long been one of the most popular medical dramas on television. Since 2005, the doctors of Seattle's most chaotic hospital have pulled at heartstrings, metaphorically and surgically. 

Of course, viewers don't only watch the show for the groundbreaking procedures and captivating ingenuity of the field's greatest medical practitioners; they watch it for the stories, the plot twists, and the emotional rollercoasters. With a staggering 84 award wins and 241 nominations, "Grey's Anatomy" is a juggernaut of primetime TV drama. The show's canonical timeline starts way back in the 1950s, and all through the decades there's drama and scandals to spare. But with nearly 20 seasons totaling roughly 400 episodes, the countless relationships and thousands of surgeries all get a little hard to keep track of after a certain point. That's also not including two successful spinoff shows, "Private Practice" and "Station 19," which are also from creator Shonda Rhimes. 

Whether you've seen enough of this dark and twisty series to be a brain surgeon yourself or you're just now jumping in for a month-long binge session, we've compiled every major plot twist and love affair for your edification. Here's the entire timeline of "Grey's Anatomy" spelled out.

Where would the talented and miracle-creating doctors of Grey Sloan Memorial Hospital be without the famous Seattle hospital? Before being renamed, one of TV's most famous institutes of health was known as Seattle Grace Hospital. Founded in 1947, Seattle Grace was established as a reputable and leading hospital with the nation's best and brightest in their respective fields.

Many of the main characters of "Grey's Anatomy" start their medical careers at Seattle's finest hospital, but their personal stories begin much earlier. Doctors Ellis Grey (Kate Burton) and Richard Webber (James Pickens Jr.) are two of the most senior doctors to have done their internships and residencies at Seattle Grace in the late 1970s and early 1980s. Ellis and Thatcher Grey (Jeff Perry) are married around this time, but an exact date is never established. Richard and Adele Webber (Loretta Devine) are married in 1978 when the two are both about 25 years old. As far as Richard and Ellis go, during their first years at Seattle Grace, they begin having a long-term affair. They bond not only over the hardships of being seen as the "others" in their field, but for the love they have for each other and the chemistry they find while working together. 

Derek Shepherd (Patrick Dempsey), Addison Forbes Montgomery (Kate Walsh), and Mark Sloan (Eric Dane) are born in 1966, 1967, and 1968, respectively. 

Born in 1978, Meredith spends the earlier years of her life with her mother and father in Seattle. During most of that time, her mother rises to become one of the most notable general surgeons in the country. But while Ellis flourishes as a surgeon, she falters as a mother to Meredith. 

By 1983, when Meredith is about 5 years old, Ellis wins her first Harper Avery Award — the most prestigious surgical award in the fictional universe of "Grey's Anatomy." In the same year, her affair with Richard reaches a boiling point when the two decide to leave their current marriages in pursuit of their own relationship. Ellis keeps her side of the promise and announces to her husband that the marriage is over, resulting in Thatcher leaving the family. Richard, however, changes his mind and decides to stay with Adele rather than run away with Ellis. In the immediate aftermath of Richard breaking off his affair, Ellis attempts suicide as a last-ditch effort to bring Richard back to her, traumatizing a young Meredith who witnesses it.

Ellis soon discovers that she is pregnant with Richard's child, unbeknownst to him. She takes Meredith and moves to Boston, Massachusetts, where she has their baby, Maggie (Kelly McCreary) in late 1983. Ellis gives Maggie up for adoption to the Pierce family. After the divorce, Thatcher meets his second wife, Susan (Mare Winningham), and they have their own children including Meredith's half-sister Lexie (Chyler Leigh) in 1984.

The year 2005 marks the first episode of the series and the start of Meredith's (Ellen Pompeo) first year as a surgical intern at Seattle Grace Hospital with other members of her class. She meets Cristina Yang (Sandra Oh), Izzie Stevens (Katherine Heigl), Alex Karev (Justin Chambers), and George O'Malley (T. R. Knight), and her teaching resident, Miranda Bailey (Chandra Wilson).

Derek moves from New York to Seattle after he catches his wife in bed with his best friend. He and Meredith meet in a bar and start a short-lived relationship for about two months until she finds out that Derek is, in fact, still married. Derek and Addison attempt to rekindle their marriage of 11 years while Meredith entertains a string of one-night stands, including one with George. Cristina and Preston Burke (Isaiah Washington) start dating within the same time frame. Cristina becomes pregnant but undergoes surgery for an ectopic pregnancy after Addison's arrives in Seattle. According to the OR board in "Make Me Lose Control," from Season 2, Cristina is 28 years old in early spring of 2006.

During their intern year, the core group encounter a series of dramatic medical disasters, but the biggest one of their careers so far is when a bazooka rocket ends up in a patient's abdomen in "It's the End of the World," sometimes casually referred to as "The 'Grey's Anatomy' Bomb Episode." 

Cristina, Meredith, Derek, and Preston are at the heart of the disaster when, after they remove it from the patient, the rocket goes off. None of them are hurt, but a member of bomb squad dies in the explosion.

In the same day as "It's the End of the World," the events of the episode "As We Know It" take place. Miranda Bailey gives birth to her son, Tucker Jr. 

As the interns' first year at Seattle Grace Hospital enters its second half, Izzie is emotionally tested as she falls for a cardiac patient, Denny Duquette (Jeffrey Dean Morgan), who suffers from a debilitating heart condition. The two get engaged as Denny's condition deteriorates and he dies on May 14, 2006. After more tumultuous ups and downs, Derek and Addison have now finalized their divorce.

A second major disaster hits the hospital when a ferry crashes into a dock. In the incident, which happens over episodes "Walk on Water" and "Drowning on Dry Land," Meredith falls into Puget Sound after trying to help an injured ferry rider and gives up any attempt to swim to safety. In the days after her accident, she finds out Ellis has died of a heart attack, around April of 2007.

In later episodes of Season 3, Meredith has her first encounters with her paternal half-sisters, Lexie and Molly (Mandy Siegfried) when Molly is admitted to Seattle Grace for her pregnancy.

Cristina progresses in her relationship with Preston, and they are on the fast track to marriage in June 2007. Preston leaves Cristina at the altar and he makes a remarkably dramatic exit from the series in "Didn't We Almost Have It All?" when Cristina comes home to find his stuff moved out.

If you or anyone you know is having suicidal thoughts, please call the National Suicide Prevention Lifeline by dialing 988 or by calling 1-800-273-TALK (8255)​.

Seasons 4 and 5 make up the first official year of Meredith, Cristina, Izzie, and Alex's residencies while George has to redo his intern year after failing his exams. Lexie joins the incoming class of interns with George, which is supposed to happen around July 1, 2008. As Season 4 continues, Meredith and Lexie get to know each other better and they navigate the different versions of their father they had experienced while growing up.

In Season 5, Meredith and Derek start up their relationship again for the long run while Mark and Lexie kick off a forbidden romance. Izzie starts experiencing severe hallucinations of Denny, which turns out to be progressed cancer. While dealing with the fallout of aggressive treatments, Alex and Izzie get married on a whim in May 2009, hijacking what would have been Meredith and Derek's wedding.  On the flip side of all the sadness, Cristina meets an impressive Army surgeon, Owen Hunt (Kevin McKidd) and they start dating. Though they hit several rocky points, as Owen struggles with PTSD.

By the end of Season 5, Derek and Meredith are pseudo-married after writing their vows on a blue sticky note, which happens in late May of 2009. George jumps in front of a bus to save a pedestrian from getting hit. As a result of taking the full force of a bus, he dies just before the end of his second intern year, around the middle of June 2009. 

Season 6 and year two of surgical residency for Meredith, Cristina, Izzie, and Alex starts with George's funeral in June of 2009. A significant shift in hospital staff comes along after Seattle Grace absorbs Mercy West and becomes Seattle Grace Mercy West Hospital. As a result, new residents April Kepner (Sarah Drew), Charles Percy (Robert Baker), Reed Adamson (Nora Zehetner), and Jackson Avery (Jesse Williams) join the core group of doctors. 

After taking a step back, Richard gives up his position as chief of surgery and is replaced by Derek who finds his own struggles in the job through the entire season. Owen and Cristina's relationship becomes increasingly strained after Owen's best friend Teddy Altman (Kim Raver) joins the hospital staff around the fall of 2009. More relationship trouble befalls Alex as Izzie has apparently taken off with no warning and he is later served divorce papers after Valentine's Day in 2010. This marks Izzie's final appearance on "Grey's Anatomy," though she is referenced in several episodes much later on.

In a two-part season finale, occurring in late spring of 2010, Seattle Grace Mercy West suffers a mass causality shooting when a deceased patient's widower attempts to take revenge on the surgeons he believes killed his wife. Over the course of both episodes, several doctors are killed, including Charles and Reed, while others, such as Derek, Alex, and Owen, are wounded. In the chaos, Meredith suffers a miscarriage of her and Derek's baby. 

Season 7 takes place several months after the Season 6 finale, "Death and All His Friends." Seattle Grace Mercy West doctors and staff start to emerge from the event of the shooting and a small, six-month time jump to Christmas of 2010 moves the characters into a time frame of post-trauma stability. Amelia Shepherd (Caterina Scorsone) also makes her first appearance during "Superfreak," the third episode of Season 7, to check in on Derek.

It wouldn't be "Grey's Anatomy" without a few love triangles spicing up the lives of several doctors. Callie Torres (Sara Ramirez), Arizona Robbins (Jessica Capshaw), and Mark Sloan find themselves in the middle of a triangle, as do Cristina, Owen, and Teddy. 

Of course, medical boundaries are there to be pushed and Derek and Meredith embark on a journey to cure Alzheimer's. Given that Richard's wife has recently been diagnosed with the disease and Meredith's mother's condition dismantled her career and personal life, a clinical trial becomes Derek's fixation. To his dismay, Meredith tampers with the clinical trial as a way to afford Adele a spot in the research and their marriage suffers as a result.

Much of the last few episodes of Season 7 take place over a 12-week period starting around March 2011. Callie and Arizona's baby, Sofia, is born in early May 2011. Zola Limbani (Jela Moore) makes her first appearance in "White Wedding" when she's about six months old. Derek and Meredith start the process of adopting her around the middle of May 2011.

As the core group of residents including Meredith, Cristina, Alex, Jackson, April, and Lexie find themselves starting the later years of their residencies during Season 8, one would think the drama is bound to cool down. But whoever thought that has never seen a show from Shondaland. 

Events in 2011 and 2012 pave the paths for many staff members of Seattle Grace Mercy West Hospital. Meredith and Derek are attempting to find solid ground to stand on after Meredith's tampering invalidates Derek's Alzheimer's clinical trial. Zola's adoption is finalized at the start of November 2011 in a heartfelt moment between the couple and their new baby that made just about everyone who watched "Suddenly," the 10th episode of Season 8, cry with vicarious joy.

Adele's Alzheimer's prognosis deteriorates, and Richard is left to continue dealing with her worsening condition. Catherine Fox (Debbie Allen) makes her first appearance during the fall of 2011 in "Love, Loss and Legacy" and she captures Richard's eye quickly after.

The residents tackle an array of crazy medical procedures and emergencies, not to mention their own philandering. That episode with the rogue lion? Crazy. The one with the twins joined at the head? Almost crazier. And when April and Jackson hook up in the bathroom at their board exams? Holy cow. 

To top it all off, the finale of Season 8, "Flight," brings on a disaster unlike any previously seen on "Grey's Anatomy."

As relationships find stability and emotions smooth out, showrunner Shonda Rhimes never takes a second to think about throwing a stone in calm waters. 

"Flight," which occurs in mid-May 2012, is an episode like no other and it threw viewers for a loop when it aired. Meredith, Cristina, Arizona, Derek, Mark, and Lexie find themselves in the wilderness after the plane taking them to Idaho for an exclusive surgery crashes. In the immediate aftermath, they have to assess their injuries, survive, and find a way home. Cristina tries to keep the peace and sanity of Arizona and Meredith but falls into a state of psychosis as soon as they return to Seattle.

The lower half of Lexie's body is stuck under a huge portion of the plane. Her injuries are too significant to fix in the field and she dies before they are rescued. Derek suffers several broken bones in his hand and arm when it's caught between severed pieces of the plane. He is forced to temporarily take a step back from surgery as a result. Arizona sustains injuries to her leg, and she undergoes an amputation when they make it back to Seattle. Meredith and Cristina's injuries are relatively minor compared to everyone else's with Meredith finding a piece of shrapnel in her leg and Cristina enduring a dislocated shoulder.

The team mourns the loss of Lexie, lovingly known as Little Grey to some, and Mark soon dies as a result of the injuries to his heart and chest around July 2012. 

Many members of the core group graduate to become surgical attendings or fellows at the hospital. Alex, Jackson, Meredith, and April fall into the different departments around the hospital — pediatrics, plastics, general, and trauma, respectively.

Cristina has left Seattle Grace Mercy West Hospital for another hospital in Minnesota in an attempt to run away from her problems, though one could argue that never really works. She eventually returns, but it's awkward since she has to face Owen again. New interns Jo Wilson (Camilla Luddington), Shane Ross (Gaius Charles), Stephanie Edwards (Jerrika Hinton), Leah Murphy (Tessa Ferrer), and Heather Brooks (Tina Majorino) arrive at the hospital and are being guided by doctors who are not only champions of their fields but are also now famous for (mostly) surviving a tragic accident.

Seattle Grace Mercy West Hospital becomes Grey Sloan Memorial Hospital in early 2013. The switch is a direct result of the plane crash settlement money that is awarded to the survivors. To save the hospital from bankruptcy and a buyout, the crash survivors decide to purchase of the hospital to keep its door open to patients, making it a hospital owned and run by doctors. That's a medical industry rarity, even by real-world standards.

The Season 9 finale finds the doctors at the heart of an impending storm which serves not only as a drama-filled season finale, but also as a metaphorical foreshadowing for Grey Sloan Memorial and its staff.

Happy times are on the horizon (for now) for Meredith and Derek after she gives birth to their second child, Derek Bailey Shepherd, in May of 2013.

Grey Sloan Memorial is an extraordinarily rough place to intern, and the new batch of would-be medical professionals is no exception. Heather and Richard are the victims of an electrocution during a major storm. Heather succumbs to her injuries and dies in July of 2013, while Richard finds himself on a long road to recovery.

Professionally speaking, Derek is at the top of his field in neurosurgery and has taken on an outstanding project to map the human brain. It doesn't go unnoticed; in early 2014, he receives a call from the president of the United States offering him more resources for the project. Derek accepts, but the job takes a toll on his marriage soon after. 

After an overly complicated and awkward fling with Jackson, April dates and gets engaged to paramedic Matthew Taylor (Justin Bruening). The two are all set and ready to walk down the aisle, at least right up until Jackson professes his undying love to April while she's at the altar. April elopes with Jackson instead of marrying Matthew in spring 2014. Not too long after, April tells Jackson she is pregnant with their child, who they name Samuel.

In her last appearance, Cristina takes a job offer in Zurich, Switzerland, to run Preston Burke's research hospital, leaving Seattle behind in mid-May 2014.

Much of Season 11 spans over several months and includes a significant time jump. The emotional blows never cease, and showrunner Shonda Rhimes tosses significant plot bombs on viewers. 

After Cristina's exit from "Grey's Anatomy," Maggie steps in to take over as head of the cardiothoracic department at Grey Sloan Memorial, around mid-to-late May of 2014. She quickly starts drawing attention to herself after it's revealed that she is the love child of Ellis and Richard, and another half-sister of Meredith. 

Advancing careers is one of the bigger themes of Season 11 and it's evident in Callie, Arizona, and Owen's careers. Callie and Owen make strides in the field of prosthetics when they work to open a robotic limb lab to help disabled veterans. Arizona meets a talented and confident fetal surgeon, Nicole Herman (Geena Davis). Nicole decides to take Arizona under her wing and teach her everything there is to know about fetal surgery. It's revealed several months into the mentorship, around mid-November 2014, that Nicole has a six-month prognosis from an inoperable brain tumor.

April and Jackson discover that Samuel has a fatal defect and the couple manage with the grief. April gives birth to her son around the start of 2015, though a date is never established. 

Amelia learns about Nicole's brain tumor and convinces her to let her operate. Nicole has passed on her knowledge of fetal surgery to Arizona. Nicole survives the surgery and emerges tumor-free but is left permanently blind.

In the earlier months of 2015, Derek and Meredith are taking things day by day as Derek commutes between Washington, D.C., and Seattle for his work.

But in April 2015, Derek stops on a narrow Seattle mountain road to help the victims of a brutal car wreck get to safety. The episode, "How to Save a Life," follows Derek as he single-handedly saves four people from two cars, triages their injuries, and nearly stays safe himself. In the last moments of the incident, just as he is about to leave the scene, a semitruck comes out of nowhere and hits Derek's car. 

He is transported to Dillard Medical Centre, where the emergency room is ill-equipped to handle five crash victims. Dr. Penny Blake (Samantha Sloyan) tries arguing with the other doctor, Paul Castello (Mike McColl), saying Derek needs a CT before abdominal surgery, but Paul ignores Penny and Derek's condition worsens while he is on the table. Ultimately, he doesn't receive the treatment he needs, and Derek Shephard dies as a result. Meredith is called and arrives with their two kids to say goodbye in a gut-wrenching scene. 

Derek's funeral occurs just days after his death and the grief is just starting to set in for Amelia and his friends at the hospital. 

Overcome with the loss of her husband, Meredith makes a sudden and drastic change when she packs up her stuff, the kids, and moves to San Diego without so much as a note to her friends or extended family. "She's Leaving Home: Part 1" and "She's Leaving Home: Part 2" cover around nine months of time that ends in February 2016. 

During the time Meredith spends in California, Alex is trying to contact her to find out where she is and if she's okay. Amelia starts to unravel as the reality of Derek's death dawns on her. Still grieving the loss of their son, April and Jackson find their relationship is starting to splinter. April takes a cue from Meredith but goes one step further and leaves the country. 

The return of Meredith occurs at the end of the second episode. It's also revealed that Meredith was pregnant and gave birth to her and Derek's third child while she was in California, in January of 2016. She says she never got the opportunity to tell him that she was pregnant and names her daughter Ellis. 

Season 11 ends with fresh beginnings as a new batch of interns start at Grey Sloan Memorial Hospital in July 2016 and Richard and Catherine tie the knot.

It's now the fifth year of Meredith and April as attendings in general and trauma. Alex and Jackson are in their third year as attendings in pediatrics and plastics-ENT, respectively. The hospital makes a shift in leadership and Miranda becomes the first female chief of surgery at Grey Sloan Memorial in October 2016. 

Season 12 is the first full season of "Grey's Anatomy" without Derek. Despite Meredith having spent a significant amount of time away in another state, much of this season is new territory for everyone who is used to McDreamy's presence. When Maggie hosts a dinner party for everyone, Penny suddenly shows up as Callie's new girlfriend and says she is joining the residency program at Grey Sloan. Furious, Meredith drops the bombshell that she is the one responsible for Derek's death. Penny spends the rest of her time at Grey Sloan trying to make up for her past mistakes. 

As fall comes to a close, Meredith is the victim of an attack by a patient in post-ictal psychosis (a state of severe aggression or confusion after seizures). She spends the next six weeks in the hospital recovering until around January or February 2017. 

As of "When It Hurts So Bad," Derek has been dead for two years. Amelia and Owen start dating and things get pretty serious pretty fast. April discovers she is pregnant with her and Jackson's second child and hits the 24-week mark around June or July 2017, after their divorce. 

Audacious scandals circle the doctors in the two years leading up to the pandemic that plagues Grey Sloan Memorial. There's never a dull moment.

Major changes take over the Harper Avery Foundation when news breaks of its titular founder's past sexual misconducts. Catherine takes charge of the foundation and its namesake award, creating the Catherine Fox Foundation and making efforts towards amends for those wronged by Harper's actions. Meredith earns her first Catherine Fox Award some weeks later in July of 2017.

Relationships are tested more than ever between Seasons 13 and 16, but there's still a lot of love to go around. Jo deals with her past catching up to her when her abusive husband shows up at the hospital asking for a divorce and Alex does his best to support her, which happens around late summer of 2017. Teddy and Owen start growing their own family when Teddy gets pregnant around June 2018. Meredith finds new love with a younger resident, Andrew DeLuca (Giacomo Gianniotti), and the two grow closer through their relationship during the fall of 2018.

As Season 16 picks up, Meredith is in hot water after she, Richard, and Alex are fired for committing insurance fraud. Alex and Richard move on by getting new jobs at Pacific General North Hospital in October 2019. Meredith is allowed back to Grey Sloan after she is brought in front of the medical board. Pretty abruptly, Alex Karev leaves "Grey's Anatomy" weeks later.

If you or anyone you know has been a victim of sexual assault, help is available. Visit the Rape, Abuse & Incest National Network website or contact RAINN's National Helpline at 1-800-656-HOPE (4673).

The staff at Grey Sloan Memorial see sweeping changes to life and medicine as they know it when COVID-19 wreaks havoc starting around April 2020. New and seasoned medical professionals find themselves overwhelmed, overworked, and exhausted as the pandemic rages into May 2020. 

The venerable main character finds herself testing positive for COVID, and her case is serious enough for her to require a ventilator to breathe. During her time under sedation, Meredith Grey dreams of all the people in her past who have already died. It's an emotional rollercoaster of joy, longing, and grief after reuniting with George, Lexie, Mark, Andrew, and Derek. Amelia tries to hold down the fort at home with Meredith's children and her own newborn, Scout. Later on in the season, Andrew dies in May 2020 after a fatal confrontation with a known and dangerous criminal during a crossover episode with "Station 19," "Train in Vain."

Season 17 is one of the show's shortest seasons, but it's also got some major parallels with what was happening in the real world at the time. Vaccine trials are underway for the staff around the summer and fall of 2020. Another time jump of eight months occurs in the season finale, "Someone Saved My Life Tonight," bringing the story to April of 2021. In that time, Owen proposes to Teddy, Maggie gets married to her fiancé Winston (Anthony Hill), and Jo adopts a baby, Luna, months after her divorce to Alex is finalized. 

"Grey's Anatomy" Season 18 visualizes a world where COVID-19 is in the past and medical advances are being made. The first episode of the 18th season, "Here Comes the Sun," starts in the fall of 2021. 

New personal beginnings, romances, and innovation are powerful overarching themes of Season 18 of "Grey's Anatomy." Meredith meets Dr. David Hamilton (Peter Gallagher) while visiting the Mayo Clinic in Minnesota and he tempts her with an innovative and groundbreaking research library and center that would be named The Grey Center. Amelia joins Meredith at the clinic to help with the research being conducted. The two spilt their time between Washington and Minnesota for the next several months and through the holiday season.

New romances are budding when Meredith finds a new beau, Nick Marsh (Scott Speedman); Maggie revels in the first few months of her marriage with Winston; Owen and Teddy finally decide to tie the knot, and Amelia finds a partner, Dr. Kai Bartley (E.R. Fightmaster) while working at the Mayo Clinic. Addison Montgomery returns to Seattle when she comes into town for research. She and Meredith reunite, and Addison finally meets Derek's kids after she admits to Meredith that she misses him. 

The second half of Season 18 starts around the 2022 New Year. The hospital starts facing shortages of doctors and supplies while Catherine faces significant audits of the hospitals under the foundation. Will things turn around in 2023? We'll have to wait and see.