Season 4 - Episode Guide

Dr. Shaun Murphy treats a patient with an illness that is not only unpredictable in nature, but also unlike anything he or the team at San Jose St. Bonaventure has ever seen before. As safety protocols and quarantines increase due to the global pandemic, Lea and Shaun's new relationship will become tested; and Dr. Alex Park gets ready to move back to Phoenix, Arizona, to be closer to his family. Meanwhile, Dr. Morgan Reznick navigates her way around the clinic following her departure from the surgery team and unknowingly puts herself and several members of the staff in danger. Finally, Dr. Claire Brown continues to work through her grief, still reeling from the sudden death of Dr. Neil Melendez.

Dr. Shaun Murphy and Dr. Marcus Andrews determine that their patient has been infected with COVID-19. As they struggle to understand and get ahead of a constantly evolving virus, Shaun has a hard time balancing his fears and concerns about potentially jeopardizing Lea's health and wanting to be with the woman he loves. Meanwhile, Claire looks for a way to grieve Melendez's death through her patients. In the COVID-19 ward, Dr. Morgan Reznick softens a little while tending to Nurse Petringa, who imparts a bit of wisdom from her 40+ year nursing career. Elsewhere, Dr. Alex Park and Mia discuss their future together.

With several candidates vying for residency at St. Bonaventure, Chief of Surgery Dr. Audrey Lim tasks Dr. Shaun Murphy, Dr. Claire Browne and Dr. Alex Park with mentoring the top first-year resident contenders. As their mentees shadow them for the day, Shaun and Park meet with Andrews to discuss a difficult surgery scheduled for a minor. Later, Shaun inadvertently insults Lea while discussing the pros and cons of the controversial surgery. And elsewhere, Dr. Morgan Reznick seeks out Claire and Lim's help on a consult.

Dr. Morgan Reznik and Dr. Shaun Murphy's pregnant patient with twins is having pain and they are forced to grapple with a decision no one wants to make. Meanwhile, Shaun asks Lea to move back in despite her reservations.

Dr. Shaun Murphy questions his decision to give the new residents autonomy when one of his intern's misdiagnosis of a patient has dire consequences. Meanwhile, Dr. Claire Browne, Dr. Alex Park and Dr. Jordan Allen treat a patient with a ruptured cyst affecting key functions of her brain. And elsewhere, Dr. Morgan Reznick and Park bond over failed relationships. 

As Chief of Surgery Dr. Audrey Lim struggles to cope with the residual emotional trauma of COVID-19, she encounters a young war veteran fighting debilitating PTSD. After discussing his case with the team, Dr. Claire Browne suggests a radical treatment to help him. Meanwhile, still reeling from the recent loss of his mentee's patient, Dr. Shaun Murphy declares he doesn't want to teach the new residents anymore. And elsewhere, an eccentric patient keeps the team entertained.

Dr. Morgan Reznik discovers her patient's wealth and obsession with extending his life is a dangerous mix that could end up costing more than he can afford.

The team treats a teenage gymnast who experiences complications from her intensive training. Meanwhile, Shaun meets Lea's parents for the first time.

The doctors are facing a challenge when a pregnant patient is admitted with an aggressive brain tumor. Meanwhile, Claire has to face some cold hard truths about how patients of color are treated compared to white patients when it comes to being prescribed pain killers and other medications. Shaun turns to Lea for advice on how to deal with the feelings he has for a Radiology resident at the hospital. 

When the hospital is hit with a cyberattack threatening to shut down life-saving machines, Lea rises to the challenge and looks to outsmart the hackers to prove herself. Meanwhile, the team treats an inspirational cancer survivor-turned-successful-philanthropist who harbors a dark secret.

After bringing in an incredibly unique and complicated spinal surgery, Dr. Aaron Glassman challenges the residents for an opportunity to join him in the operating room. Meanwhile, Shaun and Morgan disagree on how to treat a comatose patient with a cancerous tumor.

When a renowned surgeon comes to St. Bonaventure for treatment, the team's enthusiasm is quickly overshadowed by the doctor's behavior. After studying his case, Dr. Shaun Murphy sees a pattern he recognizes. Meanwhile, Shaun and Lea are forced to make a life-changing decision that will alter the course of their relationship.  .

Claire is blindsided when her absentee father shows up at her door; Shaun feels disconnected from Lea, causing tension in their relationship.

After finding out the gender of their unborn child, Lea's enthusiasm prompts Shaun to make an effort to be a more supportive partner. Meanwhile, the team treats a navy pilot whose previous doctor's misdiagnosis compromises her chances at a full recovery.

After a political protest turns violent, the team races to save two young gunshot victims.

Shaun struggles with his role as Lea's partner after complications arise with the pregnancy and his instincts as a medical professional kick in. Meanwhile, Dr. Park, Dr. Andrews and Asher disagree on how to address an elderly patient's wishes.

Dr. Claire Brown and the team must face hard truths about what lines they are willing to cross when one of Claire's idols becomes her patient.

Shaun and Lea go on a camping trip to distract themselves from their grief over their miscarriage; Morgan and Park argue about the best course of treatment for their patient.

During part one of the two-part season finale, the St. Bonaventure team travels to Guatemala on a surgical mission to help patients at a rural hospital. Once there, the team faces a small community that is in desperate need of their help but are assigned the daunting task of identifying who they can help most. And while Shaun seems to be thriving in Guatemala, Lea is still struggling with the loss of her baby.

Dr. Shaun Murphy must perform a risky surgery on a patient without electricity when the power suddenly goes out at the hospital in Guatemala. Additionally, Dr. Lim and Dr. Mateo Rendón Osma's relationship deepens as they overcome difficulties during their surgery.