Shaun's proposed treatment for a homeless patient puts him and Jared in Andrews' crosshairs. Meanwhile, Claire tries to overcome Melendez' reluctance to do a risky heart operation while Glassman must overcome his personal feelings about his oncologist, Dr. Marina Blaize, and face a difficult decision about his health.
As Shaun pushes back against Dr. Melendez in order to treat a gravely ill hospital janitor and deal with the return of Lea, Dr. Lim risks a lawsuit and her career to help a teenage girl repair the damage caused by an archaic custom. Meanwhile, Dr. Glassman exercises demanding oversight with Dr. Blaize in choosing a doctor for his brain surgery.
Shaun recalls his own past to help an intellectually disabled teenager, while Claire is put between an injured teenage rock climber and her worried parents. Meanwhile, Glassman's post-op hallucinations force him to confront a personal tragedy.
When a patient suffering from anorexia can't gain the necessary weight needed to survive heart surgery, Claire suggests they perform an experimental surgery which Melendez strongly opposes. Shaun worries Glassman's refusal to walk the hospital floor will keep him from being discharged and tries to persuade him to ambulate. Meanwhile, Shaun and Lea change the terms of their current relationship.
Morgan and Shaun's indecision on how to treat a young violinist who visits the ER with an infected finger could affect her future in more ways than one. Meanwhile, Lim, Claire and Park can't figure out if their young patient is really ill or looking for attention.
The staff tries to return to normal after the quarantine. As Dr. Lim recovers from the virus, she and Dr. Melendez must navigate through their new relationship. Dr. Murphy and Dr. Glassman try to relax and recover from their ordeals.
Dr. Andrews tries to convince a grieving mother to donate her teenage daughters face to another young girl whose face was horribly disfigured in an accident. Shaun spends a vacation day with Dr. Glassman and they end up on a road trip.
Dr. Murphy is desperate to join the team on a dangerous procedure involving a tumor removal. However, having been removed from the surgery team by Dr. Han, Shaun must use his talents to help figure out the cause of an infant's injuries.