Casey immediately has problems with his mom. She starts going out on dates and meeting up with strange men.
Dawson's brother Antonio is shot in front of her as he begins to unravel the newest drug dealer that have come to Chicago.
Kelly's ex-fiance Eric Whaley takes up a few shifts at Station 51, and he still holds a grudge against Kelly for calling off the wedding. Shay later tells Eric that Renee had cheated on Kelly, and that's why he called off the wedding.
Hermann, Otis, and Dawson buy a bar together.
Mills and Casey realize that Dawson has a thing for both of them.