Voight seeks revenge on the man who tried to kill him. A rumor causes a rift in Intelligence.

Lindsay goes undercover to catch a rogue cop who targets women at casinos. Platt risks her life in a negotiation crisis.

A car plows through a crowd outside of a concert venue and is followed by gunfire, sparking fears that it may be terror-related. Burgess spots Atwater's brother where he shouldn't be. The team works to bring peace to the community before more blood is shed.

After being tipped off about a woman running barefoot through the woods, Intelligence is led to a kidnapping victim locked up in a shipping container. The bizarre scenario leaves Voight questioning the legitimacy of the case, and sends the team on a twisted trail to get to the bottom of it.

After a van explodes during a Chicago street festival, a Muslim patrol officer Frank Toma goes missing and evidence quickly piles up pointing to his involvement. Burgess - who helped train Toma - is desperate to prove his innocence, even if that means going against her superiors.

Intelligence tracks down a vigilante killing rapists. The investigation hits home for Burgess, who begins to question if the men who attacked her sister truly paid for their actions.