A month after Voight's close brush with passing, Intelligence is overwhelmed with cases as they catch a high-stakes drug bust.

After tragedy strikes Intelligence, the unit must persevere during an adrenalized manhunt across the city.

Atwater struggles to find balance as he teams up with a forensic psychologist on an armed robbery case.

Assistant State's Attorney Chapman assists Intelligence with a sensitive investigation that drudges up painful memories for Voight.

In the midst of a momentous rainstorm, Intelligence lends support to Officer Cook when she and her partner disagree about an investigation.

Burgess is put to the test as she looks to make an advancement in her career.

Torres is haunted by his previous transgressions as Cook takes on a tense undercover assignment.

The unit learns the truth about a secret Torres has been keeping, as Deputy Chief Charlie Reid puts a focus on Intelligence.

Cook turns to her family when Intelligence faces administrative roadblocks that threaten a kidnapping investigation.

An unexpected visitor causes disruption for Ruzek and Burgess amidst an emotional investigation involving an unidentified young girl.

When a gas explosion rocks a high-rise, Chicago's first responders come out in force to rescue hundreds of civilians. It's the calamity beneath the surface, however, that sends our heroes on a race to save 40 people trapped deep underground, including two of their own.

The crossover starts on Chicago Fire S13E11 In the Trenches (I) and Chicago Med S10E11 In the Trenches (II).