Goodwin's troubles persist. Charles clashes with his former resident over a depressed patient. Lenox and Ripley treat a car accident victim who recently reunited with his college sweetheart.

Ripley and Frost uncover shocking information that conflicts with their patient's DNR. Asher facilitates an unexpected reunion. The tension between Archer and Lenox comes to a head.

Chicago P.D. steps up Goodwin's security after she's threatened online. Archer and Frost treat victims from a disciplinary camp injured during a rockslide. Maggie must deliver a teenager's baby.

Halloween chaos takes over the ED. Asher helps a pregnant woman with an autistic son. Charles clashes with Nurse Jackie on a psych case.

A familiar face returns to the ED. Ripley and Charles treat a woman with a rare disorder. Frost suspects that his patient's father is lying about his daughter's condition.

Asher treats a woman whose undiagnosed condition threatens the lives of both her and her unborn child. Goodwin receives a chilling message while battling the hospital higher-ups.