A wellness check on a family reveals signs of foul play and Upton is determined to find the parents and young daughter. As Hailey delves further into the troubled family dynamics, she finds herself reflecting on her own childhood trauma.

Halstead’s past resurfaces when a former Army colleague is implicated in a deadly blast. As the FBI launches an investigation into Roy’s disappearance, Upton feels the pressure of the secret she and Voight are sharing.

The team works together to identify the head of the brutal Los Temidos gang. Voight dives deeper into his informant Anna Avalos' past when her undercover role is threatened.

After the murder of a wealthy Chicago man, Atwater and the team dig in to uncover the truth, suspecting there is more to the story than meets the eye.

Atwater’s reactions during a tense arrest are called into question. The team must dig in to uncover key evidence that could aid in the ongoing investigation and clear Atwater’s name.

Atwater's worlds collide when a shooting at the building he owns in Burnside leaves a child dead. Atwater must confront his relationship with his father, Lew, as the brutal case forces them together.