While working at a sobriety checkpoint, Burgess finds a duffel bag full of heroin in the truck of a respected college professor who claims to know nothing about how the drugs ended up there. Voight decides to hold off on charging the unlikely suspect and Olinksy and Antonio follow up on a lead to see who is behind the drug smuggling. At District, Roman expresses his desires to become a Field Training Office to Platt and Mouse sets Halstead up with an off-duty security job working for the attractive owner of a medical marijuana clinic.