Com a partida de Cristina, uma nova médica, Maggie Pierce (Kelly McCreary), fazendo as rondas e Derek querendo se mudar para Washington DC, Meredith luta para recuperar o senso de normalidade tanto em casa quanto no hospital. Enquanto isso, Callie e Arizona chegam à uma decisão sobre a barriga de aluguel, Amelia ouve um grande segredo, Bailey se dá conta de que terá que lutar com Alex pelo lugar de Cristina no Conselho e um acidente insano faz dois adolescentes serem pegos em uma posição muito comprometedora.

Maggie tries to make a good impression but finds herself in unfortunate situations; Richard keeps hiding his secret.

Owen tries to get Callie to help Veterans Hospital patients with the robotic limb lab. Alex and Meredith's friendship makes Jo jealous. Alex and Bailey prepare to go in front of the board.

Secrets from Ellis Grey’s past come to light when Meredith watches old videos and reads through her mother’s journals. Meanwhile, Maggie rocks the hospital with an unexpected announcement; Alex gets new responsibilities and Callie focuses her attention on the Veterans’ project.

Callie and Arizona examine their marital problems and what's contributed to them. Meanwhile, Callie devotes herself to the veterans' project, Arizona strives to impress Dr. Herman, and Richard seeks guidance from Bailey.

Information about Amelia's past emerges and causes problems for her at the hospital.

Maggie and Meredith disagree with Derek about the best way to approach a patient’s case, which leads to a bigger argument between the couple. Meanwhile Callie feels responsible when one of her veterans is pushed too far and one doctor’s routine procedure results in a devastating diagnosis.

As Derek prepares for his move to DC, Meredith keeps herself busy at the hospital. Meanwhile, Jackson and April deal with difficult news, and Arizona and Amelia discuss how to best approach Dr. Herman.

April stays optimistic as Arizona begins testing on her baby; Dr. Herman plans out a crash course in fetal surgery; and Owen and Callie encourage each other to get back into the dating scene. Meanwhile, Meredith, Maggie and Bailey use the 3D printer to gain a better understanding of their patient's tumor.

After several discussions with Dr. Herman, April and Jackson must face their situation head on and make a difficult decision regarding their unborn child. Catherine arrives in Seattle and bumps into Richard at the hospital. Meanwhile, Meredith tries to find someone to take care of the kids so she can visit Derek for the weekend, and Amelia shows Stephanie some tough love when they work together on a case

Maggie gets upset when Meredith dodges her questions about DC; Bailey and Ben become concerned about Ben’s brother after he is admitted to the hospital, and Dr. Herman starts to warm up to Arizona. Meanwhile, Richard feels manipulated by Catherine.

The hospital doctors become fascinated with Dr. Herman’s case when Amelia gives a lecture detailing the intricacies of the surgery. Arizona and Herman continue to bond over the amount of cases they are trying to complete before the big surgery. Meanwhile, Bailey brings them a case of a pregnant woman who is close to her heart.

In this Amelia-centric episode, Amelia engages in the surgery of a lifetime as a crowd of doctors look on from the gallery. With Stephanie by her side, she begins operating on Dr. Herman, but quickly realizes it's far more difficult than she anticipated. Meanwhile, Bailey becomes skeptical when Arizona takes on one of Herman’s cases.

An earthquake shakes the ground at Grey Sloan Memorial Hospital, trapping Maggie in an elevator and threatening Meredith’s long streak of successful surgeries. Meanwhile, Owen gives medical advice to a child over the phone and Ben confides in Jackson.

A patient's condition sparks a conversation between Richard and Maggie about Alzheimer's disease; April and Jackson struggle to return to their normal lives and Arizona is faced with the reality that Callie is moving on. Meanwhile, Meredith reveals her biggest fears about Derek.

Meredith, rattled by the latest events, tries to figure out what to do about Derek. Meanwhile, Owen is shocked when his mother is admitted to the hospital.

A school field trip to the hospital takes a dramatic turn when the kids witness two injured cops enter the emergency room. Meanwhile, Stephanie sets her eyes on one of the chaperons, Callie operates on the leg of the police captain and Amelia must face her feelings for Owen.

Upon realizing that Owen and Amelia have been seeing each other behind her back, Meredith comes down hard on her sister-in-law causing Amelia to rethink things. Meanwhile, Catherine springs into action when a man is brought into the hospital after his wife seeks revenge on his cheating ways.

A small plane crash in Seattle causes multiple casualties and brings back horrible memories for the doctors, especially Meredith and Arizona. Meanwhile, friction between Owen and Amelia makes for an uncomfortable working situation for Stephanie.

Derek witnesses a horrible car accident and springs into action to save lives.

Meredith and the staff feel the impact of losing one of their own; Jackson struggles with April's decision; Bailey and Ben argue about their future. Months after Derek's funeral, Amelia struggles with her emotions; April plans to return; and Derek's part in Meredith's life continues to grow.

The doctors of Grey Sloan Memorial Hospital are forced to put their emotions aside when a catastrophic event occurs.

As the doctors continue to tackle an unfathomable crisis, they are reminded of what is important and are brought closer together.