The episode opened with a guy timing himself assembling a rifle the he left and went to a building in Chicago where he shot a man getting out of his car with two other people. The team was called in as the man he killed was the fourth man he killed.

Cooper and the team went Chicago to begin working on the case. They setup in the Chicago Police Department and began breaking down the unsub. Mick received a pager with the words “bang bang” on it. Just as he looked at it Cooper got a call there were two more killed.

Beth used a geo-location software and found a pattern to the snipers shootings and projected where he would go next. While clearing the people off the street Mick saw a reflection that he realized was the sniper and ducked with the civilian. The sniper got away but the team prevented him from killing anyone.

Cooper and the team figured out the unsub was the son of a sniper who had been “home schooled” the tracked down his address and found a not that looked like a suicide note; they then followed the address on a program for a memorial service for the father.

At the service the sister of the unsub explained that her brother was suppose to be there. Cooper realized that the memorial service was the sniper’s “end game” and what he had been practicing for. Cooper had everyone stay inside while they checked the building across the street. Mick saw the sniper on the 22nd floor where Cooper found him when he and Mick were staring at each other through scopes.