The Best Episodes Written By Krista Vernoff

Train Wreck victims come to Seattle Grace and all staff gets called in. Everyone deals with really weird cases. Except Addison and Izzie. They work with a woman who is pregnant.

Cristina and Burke continue to play Uncle until one of them gives in. Derek and Meredith are fighting over the reason for their sleepless nights. Meredith tries to talk to her father about his side of the story. There's tension between Alex and Addison. There is even more tension between Addison and Mark. Addison confides in Callie. Bailey wishes she didn't have to keep a secret from one of the interns. Callie rushes to be with George after she learns that his dad needs an emergency procedure. Izzie may have found 'some good to do' with her inheritance.

Desperate to help his pregnant daughter, Mark (Eric Dane) follows Addison back to Oceanside Wellness, Dell and Naomi struggle to raise their children under the same roof, and Violet and Cooper heatedly disagree on how to treat a patient on.

Meredith Grey and the team of doctors at Grey Sloan Memorial are faced with life-or-death decisions on a daily basis. They seek comfort from one another, and, at times, more than just friendship. Together they discover that neither medicine nor relationships can be defined in black and white.

The holiday season has started but not everyone is in a festive mood. This is Alex's last day in the hospital unless he passes his boards practical exam the next day, thus everyone helps him to review so that he succeeds. However, Izzie is not happy about the others helping him and Meredith has to remind her of the true spirit of the Christmas holiday. Justin is in need of a new heart. One is available but he does not want it because he does not believe Santa gave it to him as his mother said. Cristina and Burke, both handling Justin's case, have opposing views on the matter due to their different stances on religion. Despite a reconciliation with his wife, Derek isn't in a festive mood. George has a simple case of a woman who has a bleeding ulcer, he realizes that the ulcer is caused by her entourage but fails to keep them away, with the consequence that it perforates.

A gunman opens fire at a local college, sending mass casualties to the hospital; Arizona's return is not warmly received.

Cristina meets Burke's parents, the interns try to get Izzie's job back, and Addison takes a day off, a surgical patient may be living her last day. Some of the interns want to know why Bailey won't talk to Izzie. Meredith tries to decide between Derek and Finn and comes to a decision somewhat. Webber finds out that Callie has been living in the hospital and he confronts her about it.

The hospital staff is left to deal with the aftermath of George's passing. Hitting the staff hard, they all find unique ways to get through the various stages of grief. George's mom returns, faced with the difficult task of deciding what to do with his organs.

After a roller coaster car falls off the track at the county fair, the doctors at Grey Sloan tend to patients who spark memories about ghosts from their past. The series 300th episode!

Simone's wedding day arrives as Jo and Link's relationship hits a major turning point.

As preparations continue for Meredith and Derek's wedding, Izzie receives a surprise hospital visit from her handful-of-a-mother, Robbie. Meanwhile, a newly sober Thatcher visits his daughters, Meredith and Lexie, in order to make amends, and the Chief and Meredith bitterly fight over a controversial medical case.

Meredith struggles to come up with a new plan for Owen’s sister. Jo makes a surprising choice regarding Alex, and Andrew’s sister’s controversial research leads to a shocking discovery.

Meredith discovers that Derek has a problem sleeping while her father comes to visit the hospital. George's father is moving from one surgery to another. A patient named Heather checks into the hospital. Heather is 17 and has a nasty attitude that results from her medical condition and all the surgeries it has required her to have. Izzie has an emotional breakdown when she tries to hand over something very important to her. George's family comes to visit to celebrate his father's surgery. Cristina and Burke are playing Uncle.

An ambulance crash endangers the lives of the paramedics involved, as Meredith and the Chief work on-site to save them, Bailey treats a patient who refuses her help, and Ava returns for Alex and meets his other girlfriend in the process.

Meredith works furiously to save a paramedic trapped in an ambulance; Lexie holds the life of a patient in her hands; Derek must rely on a nurse to save a patient; Bailey struggles to balance her personal life with her work.

It's Halloween at Seattle Grace! There may be jokes, pranks, and/or scare tactics. Some of the women form a club based on an experience they all share. A man volunteers for what most of the doctors believe is an unnecessary surgery. One of the patients is in the hospital because they tried to carve a pumpkin in an unconventional manner.

When the plumbing springs a leak, chaos breaks out at Seattle Grace as the Chief tries to put in place new teaching methods. Meanwhile, George takes his residency exam; and Derek attempts to get Meredith's roommates to move out, much to their surprise.

The Station 19 crew jumps into action as a violent tornado rips through Seattle. Amidst the chaos, the team makes a shocking discovery buried under a tree, and Travis' first responder instincts kick into high gear at a political event.

Prue & Phoebe have their hands full when Piper is possessed by the spirit of an evil witch, on the day of her high school reunion.

Prue, growing weary of her battles to save innocents and in fighting off the Angel of Death, is forced to turn her back on a dying soul, and must come to grips with her feelings towards fate and the death of her mother.

Cristina and Meredith try to figure out if Cristina should tell Burke that she's pregnant right before Cristina faces an emergency. Alex and Izzie get closer while Meredith's mother gets too close.

Derek and Addison's relationship is rocked to the core when a former friend comes to Seattle Grace and his presence promises to shake things up for a few members of the staff. Burke and Cristina's relationship is affected when one of her secrets is outted. Alex and Izzie are having similar reactions to their closet scenes during the Code Black crisis. On top of this a cocky doctor shows up to piss Derek off in all kinds of ways. A patient is suffering from constant orgasms and her condition sparks interesting conversations among the staff. George is trying to figure out how to get Meredith to see him as more than just a housemate. Another patient, that Derek is treating, is dealing with a rare disorder and needs his parents support and understanding. Burke has a patient who inspires him to talk to Meredith and Cristina about doing what they say they will. Meanwhile, Meredith learns more about her family (in fact maybe more than she may have wanted to know) through her parents.

Derek asks Addison to work with his pregnant patient while Archer recuperates from surgery; Bailey and Naomi work together to find the cause of Sam's sudden asthma attack; Cooper, Violet and Pete treat a woman with postpartum depression.

Paige takes the Book of Shadows into her work to cast spells which help her co-workers. Meanwhile, Piper, who is filled with anger over the death of Prue and the recent actions of Paige, is possessed by a member of a supernatural band of vigilantes known as the Furies.

Phoebe accepts her new role in Cole's life, but she still sets out to save an innocent after she has a premonition and even seeks her sisters' help in protecting the man. Meanwhile, Piper's heart doesn't seem to be in it as she prepares to defend her family against any new threats from the underworld.