Meanwhile, Dr. Choi and April deal with a pregnancy scare while treating a young patient who may be going blind and Maggie confronts her cancer diagnosis.

Panic and terror continues to ravage Chicago as more victims die from a deadly flesh-eating bacteria outbreak.

The Chicago Police Department’s Intelligence unit investigates and suspects the outbreak might be an act of terrorism, as it is only affecting two hugely populated places in the city.

On April 19, 2019, NBC announced that Colin Donnell (Dr. Connor Rhodes) and Norma Kuhling (Dr. Ava Bekker) would be departing the series due to creative reasons,[24] but they would both appear in the season 5 premiere to wrap up their characters' storyline.

Series showrunners Andy Schneider and Diane Frolov said the scene in which Dr. Bekker takes her own life was the "ultimate revenge against the man that had rejected her.

[26] Following a pregnancy scare for Dr. Choi (Brian Tee) and Nurse April Sexton (Yaya DaCosta) in the first episode, the idea of having a child is "definitely part of their storyline.

"[26] Dominic Rains joined the cast in the recurring role of Dr. Crockett Marcel, "a hard-partying doctor from Louisiana".