Dr. Manning and Dr. Charles treat a teenage girl with a rapidly changing set of symptoms that has everyone perplexed. Dr. Choi and medical student Jeff Clark encounter a 19 year-old tough guy who is brought into the hospital in severe distress. Once they establish the cause of the pain, the situation quickly turns dangerous and a resolved Dr. Reese does her best to help. Dr. Halstead must deal with a difficult case that is further complicated by Dr. Stohl, who has a camera crew following him around to shoot a promotional video spotlighting the hospital.

Walker makes good on his promise to Liam to finally discuss captivity, and painful details from the past inform the present to help the Rangers eliminate a dangerous threat. Meanwhile, a new case forces Cassie to confront her aversion to dating.

Walker attempts to make this the most memorable Thanksgiving ever in the hopes of luring Stella to return home, but when the family’s annual “Circle of Thanks” turns into a circle of grievance, tensions bubble over- leaving things worse off than they began, with one member of the Walker family being rushed to the hospital.

An ominous Calling shakes up Michaela and Zeke’s party. Cal and Ben receive devastating news. Michaela, Saanvi and Eagan look for the Omega Sapphire.

As the Stones race to find the Omega Sapphire, Ben finds hope in a Calling that reunites him with a familiar face. Zeke faces a difficult choice.

The body of a 15-year-old girl is found crushed in an abandoned building after she runs away from a treatment center for troubled girls. Voight sends Halstead undercover as a guard to work from the inside at the center, where he believes the girls are trading sexual favors for something in return.

Ben lands in 1979 Chicago as Jack Armstrong, a devoted security guard to talented pop singer Carly Farmer. During Carly’s prep for a concert, it quickly becomes clear her life is in danger and Ben must determine who is trying to kill her and why.