Voight is assigned a new Internal Affairs handler, Stillwell who proves to be suspicious of Voight's actions. During an investigation involving a gambling ring Voight is forced to work with his former partner from the Gang Unit, Shi. At the same time Halsted remains fixated on Lonnie Rodiger and enlists Jin's help to gather more information. Meanwhile, Ruzek's inflated ego leads Olinsky to take him down a peg and offer a great opportunity to Atwater.

Voight pulls Halstead's badge when Lonnie Rodiger is found dead. After a car accident Severide and Clarke discover the torso of Dr. Elliot who has been instrumental in putting away high profile criminals. With Intelligence down one Sumner is given an opportunity to prove herself. Meanwhile during all the investigation Lindsay and Severide share a moment.