Connor ''Connie'' O'Brien is the main antagonist of episode Public Enemy of season 5 from Criminal Minds.
William that is the Connor's father was a sociopath and incendiary who often abused him when he was a child. In 1993, William caused a fire and killed Connor's mother, Judy, and made it look like an accident to have his life insurance. However his plan went awry and he was arrested and Connor testified against him, who put him in jail. At some point in life Connor got a job as a fellow at the Quality Cafe in Providence, Rhode Island, which allowed him to make friends with the police officers who were in the apartment across the street. A month before Public Enemy, William O'Brien, received a reduced probation sentence in 2015, that made Connor furious and start killing in public places one in the bathroom and one in the laundry room and another in a restaurant.
Connor appears in the church and approaches a Marine named Paul Collins and his family, he then approaches without him and no one notices and cuts Paul's throat and walks away no one notices that he was by the church. Connor then approaches a woman and he is about to kill her the more the bus appears and the woman gets on the bus, Connor then waves to the woman. Connor later kills a flower seller and soon he decides to become part of the crime scene, pretending to be a witness who tries to save the victim. BAU then arrives and blocks the area telling the police to detain all witnesses. Connor tries to escape when Officer Joseph Liddy tries to stop him from knowing him, Connor then kills him by stabbing in the neck. When the other officer insults him, he leaves and slays a woman in the library in front of his son. BAU then decides to falsely claim that the woman survived in order to lure Connor, knowing that he will verify the allegations, they then manage to fool Connor that when he sees Morgan running away from him, and he gets caught up in BAU, then Connor is arrested and ends up dividing the same cell of his father, William. Connor then appears in line when his prison mate gives him a knife, Connor then kills his father later when he identifies him.