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.

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.

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.

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.

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.

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.

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.