Third-year med students begin their rotation in the ED and Maggie keeps a careful eye on one of them. Natalie, whose mom's health takes another decline, tries to cover up how she broke the rules to treat her.

Carol receives a second chance at life when a new heart becomes available. Ethan and Dean find themselves in hot water with an old patient. Will faces the consequences of the stolen trial medication.

Dr. Halstead finds continued success in his trial. Dr. Charles' daughter, Anna, receives life-changing news. Noah finds himself in a situation not even April can fix.

As Maggie deals with her own trauma, she steps in to help a mother in need. Dean continues to stir the pot with more than one doctor. A patient comes to Med needing immediate treatment, but doesn't want it from them.

Dr. Charles and April team up to take on a mysterious patient in the ED. Dr. Halstead is forced to make a life-or-death decision for one of his trial patients. Dr. Marcel is confronted by his past when a former acquaintance is brought into the ED.

Dr. Choi helps a patient with chronic pain find a solution. Dr. Halstead considers a new path. Dr. Charles and Anna bond over a scary situation.

Ethan hires an old Navy colleague to join him in the ED. A final custody hearing threatens to separate Charles and his daughter. Maggie must make a choice that will change Auggie's life.

Crockett deals with a patient who ends up having more in common with him than he thinks. Will and Ethan clash over a pregnant patient with an irregular heartbeat.

Ethan teams up with an unexpected person to treat a famous tennis player who is afraid his career might be over. Goodwin's new protocols cause a stir.

An auto accident sends Goodwin into a spiral as she tries to help a young boy and his mother. Natalie's secretive behavior begins to draw the attention of Dr. Marcel and Dr. Halstead.

Crockett worries he made a surgical error when a recent transplant patient comes in with complications. Carol is once again in distress. Will and Natalie must take action to right their wrong.

Dr. Marcel and Dr. Manning lay everything on the line to assist a sick woman. Dr. Halstead faces an uphill battle in getting participants involved in his clinical trial. Dr. Choi clashes with a patient who demands absolute perfection of himself.

Will runs into trouble when one of his trial patients falls ill. His own stress and symptoms have Ethan struggling to get through the day.

Dean and Ethan respond to a scene that brings back some bad memories. When Carol's condition worsens, Natalie is willing to do whatever it takes to get her mom feeling better.

The staff adjusts to the new normal of the pandemic. Dr. Choi, Dr. Lanik and April fight on the front lines. Dr. Halstead and Hannah face a troubling reality. Dr. Charles tries to clear the air with his daughter following recent developments.

Goodwin announces a new ED Chief and the choice doesn't make everyone happy. Dr. Manning takes a stand for her patient and finds herself dealing with the repercussions. Dr. Charles tends to family affairs.