A run-of-the-mill DUI checkpoint turns up a big bust for Burgess (Marina Squerciati) on Wednesday's episode of Chicago P.D..

After Burgess stops a man (guest star Richard Thomas) who says he's on his way to deliver a lecture at a university, she immediately senses that something is off. A search of the vehicle reveals that he's got a whole lot of heroin stashed away for the trip.

Sure, a bookish college professor doesn't fit the typical profile of a drug smuggler, and he claims to know nothing about the heroin or how it got into his car. But is he telling the truth?

Check out an exclusive clip from Wednesday's episode here:

Chicago P.D. airs Wednesdays at 10/9c on NBC.