The Intelligence Unit discover a drug smuggling operation when a balloon filled with cocaine bursts inside a student drug mule; tensions rise between Olinsky and Ruzek.
Severide attempts to prove his suspicions about the arsonist's identity, Casey adapts to his new lifestyle, and Dawson goes on a date with a regular from the bar.
Dr Choi is affected by the outcome of gang violence; Dr Halstead is encouraged by a patient's cheery disposition; Dr Manning and Rhodes think that two cases of illness could be connected.
Voight calls the team to investigate a homicide involving the only witness in a rape and murder case against an extremely wealthy young man.