A community parade turns deadly; Maura does not seem like herself; Lt. Col. Casey Jones reveals some shocking news.
The team must probe an unusual murder case while thinking of the best way to say farewell to the late Detective Frost.
Did Garcia steal Dangle's husband? An update on Wiegel's Baby.
Frustrated with driving Carol around, Nathan insists that she learn how to drive or get a new chauffeur. Adam and Carol form an unexpected bond when he takes over her transportation.