Mia Park

When a car unexpectedly smashes through the ambulance bay doors, Dr. Choi makes some difficult decisions in an effort to save a worker trapped beneath the wreckage and April, who's also in danger.

Manning and her three-year-old patient are trapped in a helicopter as the toddler's stats decline; Charles isn't sure Choi's alcoholic patient with liver failure has quite hit rock bottom.

Dr. Charles and Caroline set some major plans; Ava fights to keep her relationship with Connor; Agent Lee informs Will of news that may put his life in danger.

Dr. Charles and Dr. Manning disagree on how to handle a patient who they discover is poisoning herself; Dr. Rhodes throws some serious accusations at Dr. Bekker; Dr. Halstead has suspicions about Natalie's new boyfriend; Dr. Choi tends to Bernie.

An alarming phone call prompts Rhodes to rush out of an important surgery; Halstead comes to the aid of an FBI agent who is brought into the ED; Manning and Choi find themselves on opposite sides of a disagreement over doctor-patient confidentiality.

Halstead treats a woman on the verge of freezing to death; Dr. Charles' ex-wife receives some concerning news; Choi handles a lymphoma patient with viral meningitis and a complicated family; Manning makes a house call.