Seattle Grace Hospital is filled with employees given the task of saving lives. In the hospital, young interns are working to become full fledged doctors. Bonds of friendship and romance are formed within the workplace. Meredith Grey's career has a rocky start as she sleeps with Derek Shepherd, who later turns out to be a surgeon at the hospital. Derek has problems pursuing a relationship with Meredith after the emergence of his estranged wife, Addison. Another intern, Cristina Yang, develops commitment issues having a relationship with interim chief of surgery, Preston Burke. George O'Malley, another intern, struggles to build his confidence as a person responsible for saving people's lives.

A forbidden kiss. A house of candles. The breakdown of stubborn man. What's going to happen next to the doctors and interns of Seattle Grace Hospital?

Dr. Webber lays out new rules for the staff and the ceiling caves in.

Derek tries to feel more at home in his new place, Alex and Izzie fight over a patient, Cristina finds a secret paradise, and George gets his test results back.

Derek and Meredith get in a fight over credit, Izzie and Alex fight over compassion, and Callie asks Sloan for help pleasing a woman. The doctors also must work as a team to conduct 12 simultaneous operations.

Seattle Grace has a new doctor who rubs the rest of the staff the wrong way while Miranda takes her first step taking on the role as the chief surgeon.

Izzie tries to save a man whose heart she gave away to Denny while the staff competes for the chance to perform their first solo surgery.

Hahn quits as two new employees, one an old friend of Meredith's, join Seattle Grace.

Lexie and the other interns find themselves going too far when Sadie's life is threatened during one of their unsupervised experiments.

Cristina is chosen to do her first solo surgery but she must find a replacement, Alex confesses something to Izzie and Lexie confesses something to Sloan.

A death row prisoner becomes a patient at the hospital while Izzie shares her secret lover with Alex.

Bailey, Alex and Arizona work on a sick child while Meredith finally meets Derek's mother.

Bailey begs Derek to forget his oath so she can save a young boy while Izzie's relationship with Denny becomes distracting.

Bailey learns that she is up for a promotion while Derek prepares to pop the question.

Addison's brother Archer is brought to Seattle and Derek is asked to save his life while Izzie tries to encourage the interns.

Derek and Addison work together to try to save a mother and her unborn child while Izzie discovers that her patient's problem has become her own.

Izzie has her interns diagnose Patient X while Alex has a breakthrough in the OR.

Bailey send reinforcements to try to get Derek to come back and Cristina struggles to keep Izzie's secret.

Derek returns to work to perform a life saving operation on Izzie while Owen has dangerous night terrors.

Izzie starts her cancer treatment while Sloan and Derek continue their cold war.

Izzie's mom comes to visit while Meredith stands up for a daughter who shot her dad 17 times.

Everyone prepares for Derek and Meredith's big wedding while a car load of college students are admitted to the ER after an accident and Izzie fears that she has taken a turn for the worse.

After spending time with another cancer patient, Izzie debates whether she wants to undergo a risky operation, Sloan decides he wants his relationship with Lexie to go to the next level, and Owen questions his place at Seattle Grace.

Everyone waits to see how Izzie's surgery went, Bailey is accepted into the pediatric fellowship program, and George is hit by a bus which leaves him in critical condition.

Izzie is brought back to life while another doctor becomes braindead after an accident. The doctors treat a woman who lost several of her limbs and a boy with growing pains.

Cristina becomes grumpy since Hunt isn't allowed to have sex with her. Webber fears that he is going to lose his job to Derek. Lexie continues to rehabilitate a woman who lost her limbs.

Izzie returns to work during a time where cutbacks are rumored. Cristina teams up with Arizona in hopes that she won't lose her job.

Meredith is forced to make a crucial decision to forgive her dad and provide him with a new liver. Meanwhile, Izzie pushes Hunt into applying her experience of survival to another patient.

The staff of Mercy West start to arrive which creates a clash with the other doctors. Izzie is betrayed by a new employee and her own mind while treating a patient.

Webb questions the doctors to learn why one of their patients who can have been easily treated died.

Derek defies Webb as he operates on a co-workers life threatening tumor. Meanwhile, Alex makes a desperate attempt to meet with Izzie.

Arizona reluctantly treats a child whose parents are going to give the hospital a large donation. Meanwhile, Cristina ignores Hunt's orders and operates on a patient.

Izzie returns to the hospital, but doesn't want to see Alex. Webber's wife suspects him of having an affair. Cristina doubts the abilities of the new cardio surgeon who worked with Hunt in Iraq.

Sloan learns that he is a father of a eighteen year old girl. Webb starts giving Meredith private surgery lessons. Cristina notices that Teddy and Owen have feelings towards each other.

Mark calls in Addison to operate on his unborn grandson. Webber spends all his free time with Meredith. Cristina is left on her own while Teddy watches her struggle with a heart valve patient.

Izzie returns home to try to work it out with Alex. Meredith orders Derek not to report Webber's drinking problem. Callie gets the chicken pox. Cristina is forced to choose between Hunt's love and Teddy's teachings.

Derek starts his first day as the new chief of staff. After a patient wakes up during surgery, Bailey panics and blames Ben, her anesthesiologist. Owen blocks Cristina from working with Teddy.

The staff adapts to change while dealing with a flood of patients after a restaurant collapsed. Mark and Callie offer Sloan to take care of her baby. Lexie gets a new look.

Derek offers Webber a job, but as his subordinate. Webber, Bailey, and Callie recall how they first started at the hospital.

A legendary doctor demands Webber operate on him. Lexie and Mark use sex to forget their pains. Arizona makes a new friend.

Owen and Webber compete over who will be able to perform a risky surgery. Mark wants to have children. Bailey is anxious about her third date with Ben.

Owen remembers his time in Iraq with Teddy. Webber feels out of place at the hospital.

Alex's brother Aaron stops by and has emergency surgery performed on him. Owen gets upset at Cristina during surgery.

After Sloan delivers her baby, Mark refuses to call his adopters and give him up. Teddy feels threatened after Derek brings in a legendary cardio surgeon to interview for her job. Calleigh tries to convince Arizona to have children.

The hospital staff is tested for their sensitivity after they receive an overly obese patient. Derek's past comes back to haunt him after the wife of a dead patient sues. Cristina is forced to deal with the daughter of a sick mother.