Owen and Link treat an older woman who wakes up from surgery and can’t stop singing, while Teddy helps Koracick stay afloat after an estranged loved one from his past comes to the hospital looking for help. Meredith, Bailey and Maggie focus their efforts on a difficult patient with a tricky diagnosis.

Jackson shares his big news with his colleagues while Koracick and Levi fight to save a pregnant woman’s grandfather as she goes into labor. Maggie keeps a watchful eye on Meredith as Bailey and Richard put off telling her about DeLuca.

Richard recruits Meredith and Bailey to help him launch a new program. Meanwhile, Addison’s patient has complications from a procedure, and Jo helps a woman who goes into premature labor.

Bailey faces an unhappy Catherine who is facing audits for several of her Foundation hospitals. Meanwhile, Addison is back at Grey Sloan; tensions rise between Meredith and Richard, and Owen returns to work.

Simone is met with a life-changing decision upon the return of someone from her past. Blue shadows Maggie on a risky procedure, while Jo and Link tend to a pregnant woman. At the intern house, Lucas and Mika throw a party filled with surprises.

Bailey tells the interns they must complete dozens of basic procedures before being allowed back in surgery; things are awkward between Simone and Lucas; Amelia comes up with a solution to a complicated surgery.

Meredith and Amelia work to secure funds for their research while Amelia finds herself at odds with a new attending. Levi runs into someone from his past, and Owen gives Winston advice. Lucas ditches Mika, forcing her to treat a patient alone.

In the midst of a deadly heat wave, the team at Grey Sloan struggles to keep up with an overwhelming amount of patients. Amelia and Winston face a challenging surgery, while Jo and Lucas run an errand for the hospital that takes an unexpected turn.

Amelia undertakes a high-risk brain surgery on a young patient, while Winston and Jules disagree over how to handle their trauma patient's family. Jo and Link struggle with wedding planning.