Dr. Halstead revives a "do-not-resuscitate" terminally ill cancer patient, and the repercussions prompt his quick removal from the case and a pending lawsuit against Chicago Med. A homeless man's arrival is passed down to April and an uneager Dr. Reese, but the circumstances surrounding his short stay catch both off-guard. Following the assessment and treatment of a bi-polar patient with an unhealthy dependence for lithium, Dr. Choi's own personal issues come to the surface, prompting him to seek the advice of Dr. Charles. The medical staff is shocked to learn one of their own has life-threatening disease.