Voight and the team attempt to hunt down the leaders of a deadly drug ring as Chicago is swept by an epidemic of heroin overdoses.
Hank works his first shift at the emergency room in years, while Jeremiah bonds with his patient and Divya worries about Lena.
Hank treats a stubborn politician, while Divya's future is impeded. Meanwhile, Jeremiah returns and Eddie has a surprise for Hank and Evan.
When Diana's hacked records go viral, Evan handles the aftermath. Later, Divya helps Jeremiah and his parents, and Hank and Jen go on a first date.
As Boris prepares to leave the Hamptons forever, he asks Hank to join him. Later, Evan and Paige consider a life-altering decision as Divya receives news.