Dr. Rhodes begins his cardiothoracic surgery fellowship but gets off on the wrong foot with his new boss; Dr. Choi begins his life as chief resident; Sarah is caught off-guard by Dr. Charles; April tries to deal with her recently discovered illness.
Drs. Manning and Rhodes suspect that two separate cases involving sick babies may be connected; a homeless patient's upbeat disposition enlightens Drs. Halstead and Charles; Dr. Choi and a Navy corpsman deal with the toll of gang violence.
An Indonesian man who doesn't speak English arrives at the hospital with a mysterious illness; Dr. Halstead attends Maggie's family reunion; Dr. Rhodes accepts a complicated heart surgery without consulting Dr. Latham.
When several patients turn out to have the same rare infection, Dr. Charles' epidemiologist daughter comes in to consult; an elderly patient's son and young girlfriend disagree over his treatment; Dr. Reese tries to help a young drug addict.
A car crash at the Chicago Marathon leaves victims in critical condition; April and her medical resident brother must perform an intense operation in the field; an 8-year-old girl experiences sudden hearing loss; Dr. Choi treats a malnourished woman.
A young cancer patient struggles to tell her parents about her condition; Dr. Reese turns to Dr. Charles and Detective Lindsay for help with a troubled young man; a teen science geek and her friends impress Dr. Choi and Natalie.
Goodwin reunites with her childhood sweetheart; Dr. Halstead gets lured into a concierge doctor app idea; Dr. Rhodes treats a woman with a heart infection against the advice of Dr. Charles; a former patient of Reese's reaches out for help.
Halstead and Manning deal with two feuding brothers, one of which is in dire need of a kidney; a patient of Dr. Reese's comes to a crossroad; a 16-year-old with a genetic condition needs surgery, but the overprotective mother gets in the way.
Dr. Charles is tasked with evaluating a patient as a possible heart recipient; Jeff makes a confession to Dr. Manning; two MMA fighters arrive at Chicago Med in bad shape; Dr. Stohl returns from his sabbatical.
A heart transplant patient gets into a car accident, revealing issues that could complicate her surgery; the police officer who arrested Maggie is brought to Chicago Med with a serious injury.
On a busy night, Dr. Reese deals with having to pronounce several patients dead; April is pressured to slow down; Dr. Charles has important news for Dr. Latham; Goodwin asks Dr. Rhodes to help an unusual patient.
A girl's rapidly changing symptoms have everyone perplexed; a 19-year-old tough guy is in severe distress; Dr. Halstead deals with a difficult case, and Dr. Stohl is followed by a camera crew that is shooting a promotional video.
Dr. Rhodes persuades Dr. Latham to accompany him on a medical trip out of town; an 8-year-old cancer patient wants to give up his battle; a woman with a personality disorder complicates a case.
A traumatic multi-car accident during a blizzard stretches the hospital staff to the limit; Rhodes and Latham make difficult decisions in triage; Choi handles a severely burned patient who has a final request.
Dr. Rhodes cares for a trauma patient whose accident is a media sensation; a grieving widower relies on a superhero costume; April pushes Halstead to use unproven medications to help a patient with no other options.
Dr. Reese is contacted for help by a troubled teen in a psychiatric facility; Dr. Manning tries to help parents make a decision about their comatose daughter's surprise pregnancy; April begins to deal with repercussions from her personal life.
Doctors and nurses deal with a staff member's suicide; Choi and Halstead face off over how to treat a patient who is experiencing stroke symptoms; Manning treats a boy who fell into the river; Rhodes examines the man who saved Dr. Manning's patient.
Will confronts a moral decision when his former teacher faces a life-threatening disease; Rhodes disagrees with the father of a young patient about a risky procedure; an unusual case causes Sarah to recall Jason Wheeler's suicide.
Doctors must diagnose patients without the aid of technology after a hacker shuts down the hospital computer system; Goodwin gets a visit from her ex husband Bert and his new girlfriend; Choi and Noah have to remove a bullet from a gunshot victim.
Dr. Halstead's father is admitted to the hospital against his wishes; Dr. Charles gets involved when his daughter's strange behavior continues to intensify; Dr. Manning feels the impact of being a working mother.
A mother is desperate to help her daughter beat cancer; Dr. Charles asks Sarah to conduct his daughter Robin's psych evaluation; Dr. Choi puts pressure on Noah when a residency spot becomes available.
Dr. Rhodes challenges Dr. Charles and other hospital staff over treatment for Robin; Dr. Manning seeks help from Detective Halstead when a sensitive case involving a young girl turns into a crime; Goodwin helps a friend in distress.