In a Duffel Bag

S3, E20: Responding to a call about a suspicious duffle bag at the Chicago Lakefront, Voight (Jason Beghe) is horrified to discover that the bag contains the frigid and unmoving body of a newborn baby. Determined to find the culprit who abandoned the infant, Intelligence receives a promising lead based on information provided by Chicago Med and Ruzek (Patrick Flueger) helps zero in on a potential suspect. Meanwhile, Voight is surprised to hear that his son is in town and Burgess (Marina Squerciati) and Roman (Brian Geraghty) grow closer.