The grand opening of Chicago Med's emergency department is interrupted by victims of an elevated train crash, pushing the staff to their limits.

Dr. Choi treats a teen mother who abandoned her newborn baby in an alley, as the staffers must make difficult decisions about the teen's future. Also, a hypochondriac with chest pains is treated, as is a patient suffering from possible dementia.

Dr. Rhodes must confront his past when he treats a close family friend who's been impaled by glass in a case that reunites him with his sister. Meanwhile, a musician must decide to undergo surgery that will save her life but could destroy her hearing.

The doctors treat victims of a movie-theater shooting as Sharon Goodwin tries to keep the press at bay. A teen with an eating disorder is treated, but Dr. Charles' methods rub others the wrong way. The staffers deal with a racist patient.

A member of Firehouse 51 clings to life and takes a sudden turn for the worse as medical staffers race to give treatment. Meanwhile, Dr. Natalie Manning prepares for her pregnancy and members of Chicago P.D. probe the case of a woman pulled from a fire. The crossover starts on Chicago Fire S04E10 The Beating Heart (I). It continues on Chicago P.D. S03E10 Now I'm God (III).