Eph investigates Kelly’s disappearance and struggles with what he finds. Dutch pursues a plan to retaliate against Palmer, and Fitzwilliam makes a surprising choice.

As Derek begins his role as interim chief, he faces a potential lawsuit when Bailey and Meredith’s patient awakens from anesthesia mid-surgery. Meanwhile, Teddy refuses to place Cristina on her…

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….

Several weeks after her near-death experience, a recovering Izzie returns to work. Meanwhile, nervous that there will be layoffs in the hospital in the wake of an announcement from the…

As Meredith, Derek and all of their friends prepare for the big wedding, a group of college students, injured in a car crash as they were heading to their graduation…

Now that Derek has the engagement ring, he searches for the perfect way to propose to Meredith, as Lexie demands that Mark go public with their relationship, and Bailey, encouraged…

Addison, Naomi and Sam rush the ailing Archer to Seattle Grace and reunite with old friends Derek and Mark to help save his life; meanwhile, Izzie employs her fellow doctors…

Derek’s confidence is shaken like never before as he faces off with Addison over what course is best for their dying pregnant patient; Cristina calls the abilities of a renown…

Derek decides to quit after learning that more of his patients have died than survived; Izzie’s interns make an unsettling discovery about “Patient X.”

After his fellow surgeons try and fail to bring Derek back to work, Meredith must summon the strength to convince him. Meanwhile the hospital is abuzz as Mark attempts a…

All eyes are on Derek as he is set to perform his first surgery after his breakdown; attention is also set on Izzie, whose medical condition requires her to undergo…

One of Meredith’s oldest friends, Sadie, becomes an intern at Seattle Grace, but Mer’s friends are less-than-welcoming to her.

Meredith, Cristina and Bailey come to Lexie and Sadie’s rescue when a routine surgery goes horribly wrong, as Owen and Derek treat a man seriously injured while sleepwalking and Mark…

Bailey teams with Seattle Grace’s new pediatric surgeon, Dr. Arizona Robbins, to save the life of a young patient near and dear to her heart, as the admittance of a…

Derek’s mother, Carolyn, makes a surprise visit to Seattle and meets Meredith for the first time, as Mark tries to conceal his relationship with Lexie from her as well; meanwhile,…

Bailey grows desperate as a patient’s condition becomes more and more dire. Everyone in the hospital is stepping up to try to find the boy a new organ donor, including…

As Meredith and Derek begin to find that their “happily ever after” is anything but easy, Cristina develops a crush on a military doctor who brings in a trauma patient….

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…

Meredith is sent into a state of panic when Derek finds her mother’s diary in the house. Meanwhile, Callie stresses while preparing for her first date with Erica. Later, Cristina…

Bailey heads up a “domino procedure” in which each surgery hinges on the one preceding it. Meanwhile, Derek gets sole credit for the brain-tumor study he did with Meredith; Lexie…

The chief gives Bailey new power and responsibility. He also gives her a very difficult surgical assignment: remove a girl’s inoperable tumor. Meanwhile, new trauma chief Owen (Kevin McKidd) challenges…

A couple undergoes surgery. Derek and Meredith’s clinical trial gets a second shot from a new patient. Izzie helps Alex. McSteamy hooks up with someone.

Addison visits Seattle Grace because they need skills that only she has. Rebecca/Ava returns with news for Alex. Meredith and Derek’s clinical trial experiences one or two developments.

The doctors meet the world’s oldest intern. Marcy brings in her son Henry because she finds his change in behavior suspicious. A patient named Connie may lose her vocal chords…

A face familiar to one of the year-twos shows up and dredges up issues that were never really dealt with. A teen soccer player needs counseling because of his father…

There has been a bus crash and the patients are in the ER. Meredith and Derek’s relationship gets more complicated when he dates a fellow doctor. Meredith’s dad goes to…

Entering their first year as residents, Meredith Grey, Cristina Yang, Izzie Stevens and Alex Karev now have interns of their own to mentor. Among the new interns are George, forced…