The tenth season of the American television medical drama Grey's Anatomy began airing in the United States on the American Broadcasting Company on September 26, 2013, and will consist of 24 episodes.
The Grey Sloan Memorial Hospital doctors are faced with the devastation left by the storm. A giant mudslide in Seattle injures a group of first responders and citizens, causing the already shorthanded ER to spring into action.
Callie makes a decision about her relationship; the doctors receive devastating news.
Meredith and Derek adjust to life at home with a newborn but find it difficulty being away from the hospital; Arizona tries to takes steps to fix her broken marriage; Alex and Jo navigate through their new relationship; and Owen clashes with Jackson over financial issues at the hospital. Meanwhile, April anxiously awaits her boards results.
The doctors of Grey Sloan Memorial throw a fundraising gala which turns wildly competitive after Jackson makes a rash promise. Back at the hospital, Bailey's patience is tested when she has to deal with several extremely difficult patients. Meanwhile, Shane and Stephanie handle an incredibly busy ER by themselves and Alex reveals an emotional secret to Jo on a very special 200th episode.
Meredith jumps back into work but finds it hard to excel at both motherhood and being a surgeon. Stephanie tries to make a good impression on Jackson's mom, and Jo finds herself overly involved with her new patient. Meanwhile, Callie and Owen deal with an emotional situation regarding a patient.
Derek and Callie work on a brain mapping project, Richard encourages the interns to use his physical condition as a learning tool and after a discussion with Callie, Meredith considers continuing her mother's research. Meanwhile, Shane continues to feel guilty about Heather's death.
Costumed patients create a challenge for the doctors; Derek and Ben work on a new surgical technique; Richard asks a resident to perform his next surgery, angering Bailey.
The issues between Meredith and Cristina hit a boiling point when one of them ultimately betrays the other at the hospital. Derek tells Jackson that he needs to let go and allow the second year doctors to work on his patients, and April and Matthew make a bold decision about their relationship. Meanwhile, Bailey has difficulties with Ben’s return.
When an unexpected malpractice suit turns Callie's world upside down, her supportive father (Hector Elizondo) arrives and shares an interesting secret with her. Meanwhile, through flashbacks, we learn some surprising details about Callie and Arizona's marriage.
Ben worries that an innocent conversation with Derek could end up causing problems for Bailey; Cristina turns to Shane as tension with Meredith increases; April's upcoming wedding creates an uncomfortable situation for Stephanie and Jackson.
April’s sisters arrive to help celebrate April’s upcoming nuptials and quickly get on her nerves. Matthew and Jackson are forced to work together when they witness a terrible accident. Callie and Arizona work hard to reestablish their relationship and Cristina is pressured to live stream an upcoming surgery. Meanwhile, a familiar face returns to the hospital.
On the day of April's wedding, the Grey Sloan Memorial doctors are all preoccupied with their own drama. Meredith and Cristina continue to argue about their research and careers, Bailey comes clean to Ben about her feelings regarding him moving back to Seattle, and Shane puts himself in a risky situation.
Alex hears news about his dad and becomes angry. Meanwhile, Derek doesn't keep a promise, leaving Meredith feeling betrayed. Arizona and Callie make a decision about their relationship and Bailey uncovers the real reason why Ben returned to Seattle.
Owen announces to the entire hospital staff that the board has passed a “non-fraternization” policy. All relationships with coworkers are discouraged. All relationships between superiors and subordinates are strictly prohibited. The surgical residents pepper Richard with questions about the non-fraternization policy. Well, Jo does. She’s ticked because her relationship with Alex just became illegal. She ends up having a big blowout breakup with her boyfriend for everyone to see. It was all a ruse though. Jo and Alex are fine.
Arizona has a bad day which escalates when she advises one of Callie’s patients on a potential double amputation. Derek goes back on a promise to Callie, and Jo and Stephanie come across an abandoned baby outside the hospital. Meanwhile, the doctors deal with the repercussions of the non-fraternization rule, which include meetings with HR and one doctor’s suspension.
Bailey asks Richard to join her on the case of a lifetime; Meredith decides to hire a research assistant; Callie shocks Derek; a young pregnant woman (Keke Palmer) needs Shane's help.
Cristina envisions two different scenarios for her life based on one crucial decision she faces. Meanwhile, a patient decides whether to live or die.
The doctors are exposed to flu-infected patients; Derek prepares to give a speech; a new doctor gives Alex a glimpse into an alternative medical practice.
Cristina won't let herself get excited when she is nominated for a Harper Avery award; Alex thinks about making a change; Callie and Derek work with a machine that recognizes emotions.
Cristina enlists Meredith to help her prepare an acceptance speech for her possible Harper Avery win and while Owen offers to attend the ceremony with her, she insists on going alone. Meanwhile, Derek feels overwhelmed between his responsibilities at home and at the hospital. April and Jackson come to a disagreement on children and religion, and Callie and Arizona try to reconnect in their marriage.
Jackson is given the daunting task of delivering disappointing news.
Cristina considers her future at the hospital; a surgery involving conjoined twins.
Meredith learns Amelia's true feelings about Seattle; Bailey deals with consequences.
The doctors bid Cristina farewell; a possible act of terrorism rocks the city.